Isan language

Thai depiction of Phra Isuan who is revered as guardian of Isan or 'the northeastern direction'.

In official and academic contexts within Thailand, Isan is treated as a dialect of the Thai language and referred to in Thai as Phasa Thai Tawan Ok Chiang Neua (ภาษาไทยตะวันออกเฉียงเหนือ /pʰaː săː tʰaj tàʔ wan ʔɔ`ːk tɕʰǐaŋ nɯːa/), 'Northeastern Thai language', or Phasa Thai Thin Isan (ภาษาไทยถิ่นอีสาน /pʰaː săː tʰaj tʰìn ʔiː săːn/), 'Thai language of the Isan region'. In common speech, Thais generally use the terms Phasa Thai Isan (ภาษาไทยอีสาน), 'Isan Thai language' or 'Thai language of Isan', or simply Phasa Isan (ภาษาอีสาน /pʰaː săː ʔiː săːn/), 'Isan language'. 'Isan' derives from อีศาน which in turn is a derivative of Īśāna (ईशान), which in Sanskrit refers to both the 'northeast direction', i.e., northeast of Bangkok, as well as an aspect of Shiva as guardian of the northeastern direction. It also references Isanapura, capital of the Khmer kingdom of Chenla that ruled the region prior to the Tai migrations. 'Isan' initially only referred to what is now southern Isan but was later applied as a convenient appellation for the entire region, people and their language as it marked them as Thai and reduced the ambiguity of which Lao people were being referred to, but also to maintain distinction even when the term 'Lao' was no longer permitted as a census category by citizens of Siam.[4][11]

Thai speakers may also casually refer to the language as Phasa Lao (ภาษาลาว /pʰaː săː laːw/), 'Lao language', but this is generally considered offensive by Isan people. As Isan people have suffered discrimination by Thai citizens from other regions, particularly Bangkok and the large Thai-Chinese minority, its use is considered very offensive, as 'Lao' is used as an insult, usually re-enforcing negative stereotypes of poor command of the Thai language, laziness, stupidity, poverty and religious zealots. The term 'Lao' is better avoided unless one is familiar with Isan people on intimate terms. The phrase Phasa Ban Nok (ภาษาบ้านนอก) /pʰaː săː bân nɔ̑ːk/, which can translate as 'rural', 'upcountry' or 'provincial language' may also be used by Thai speakers to refer to the Isan language, but is also used for any rural, unsophisticated accent, even of Central Thai.[12]

To Lao speakers in Laos, the language is acknowledged as Phasa Lao (ພາສາລາວ /pʰáː săː láːw/), but is distinguished from the language of Laos by usages such as Phasa Lao Isan (ພາສາລາວອີສານ /pʰá ː săː láːw ʔiː săːn/), 'Isan Lao language' or 'Lao language of Isan' or Phasa Thai Lao (ພາສາໄທລາວ /pʰáː săː tʰáj láːw/) which can mean 'Lao people's language', 'Lao Thai language' or 'Thailand's Lao language'. 'Lao' is also the general term in use by other linguistic miorities of the region, although in international languages, 'Isan' or translations of 'Northeastern Thai language' are used.[9][10]

An ethnic Isan woman walking her water buffalo to pasture. Isan people are primarily engaged in wet-rice agriculture, despite arid conditions and a flat topography that makes it prone to flooding during heavy moonsoons.

Isan people traditionally refer to their language as Phasa Lao (Northeastern Thai: ภาษาลาว /pʰáː săː láːw/), 'Lao language', or Phasa Tai Lao (ภาษาไทลาว /pʰáː săː láːw/), 'Lao people's language'. The language is also known as Phasa Thai Lao (ภาษาไทยลาว), 'Lao Thai language' or 'Lao language of Thailand'. The term 'Lao' is derived from an ancient Kra-Dai loan word from the Austroastiac languages, *k.ra:w which signified a '(venerable) person' and is the ancestor of the not only 'Lao' (ลาว, ລາວ) in reference to the Lao people, Lao language or the country of Laos but also the third-person pronoun 'he'/'she' as well as hao (เฮา, ເຮົາ, /háo/), the plural first-person pronoun 'we'. 'Tai', 'Thai' and related forms 'Thay' and 'Dai' derive from another Austoasiatic loan word into Kra-Dai, *k.riː which also signified 'person' or 'free person'.[13]

Due to prejudice and stigmatisation of the spoken language by Thai people of other regions, Isan speakers only refer to themselves and their language as 'Lao' when in a comfortable environment where they can speak the language freely, such as anywhere in Isan or in the company of other Isan people in more private settings, such as a family home or groups of friends from the region visiting one another. To prevent confusion with Lao people of Laos and use a more neutral term, Isan people also use Phasa Thai Isan (ภาษาไทยอีสาน /pʰáː săː tʰáj ʔiː săːn/) or simply Phasa Isan (ภาษาอีสาน) when in mixed company or outside of Isan. Younger generations are more apt to forsake any Lao identity and have generally switched to the regional Isan designation for themselves and their language. The language is also known poetically and affectionately as Phasa Ban Hao (ภาษาบ้านเฮา, /pʰáː săː bȃːn háo/) which can signify 'our home language' or 'our village language'.[14]

Traditional dwelling of Tai Dam in the Mường Thanh Valley, northern Vietnam. The Vietnamese name Mường Thanh is from the local Tai form of Mueang Thaen, the 'City of the Gods' and birthplace of Khun Burom in the Tai legends of Southeast Asia.

The ancestors of the Lao people were speakers of Southwestern Tai dialects that migrated from what is now southeastern China, specifically what is now Guangxi and northern Vietnam where a diversity of various Tai languages suggests an Urheimat. The Southwestern Tai languages began to diverge from the Northern and Central branches of the Tai languages, covered mainly by various Zhuang languages, sometime around 112 AD, but likely completed by the sixth century.[17] Due to the influx of Han Chinese soldiers and settlers, the end of the Chinese occupation of Vietnam, the fall of Jiaozhi and turbulence associated with the decline and fall of the Tang Dynasty led some of the Tai peoples speaking Southwestern Tai to flee into Southeast Asia, with the small-scale migration mainly taking place between the eighth and twelfth centuries. The Tais split and followed the major river courses, with the ancestral Lao originating in the Tai migrants that followed the Mekong River.[18]

The Tai migrants assimilated and intermarried with the indigenous Austroasiatic peoples or pushing them off to marginal areas, but their full expansion was halted by the Indian-influenced kingdoms of the Mon, Khmer and Cham, although the Khmer were the primary power in Southeast Asia by the time of the Tai migrations. The Tai formed small city-states known as mueang (เมือง, ເມືອງ muang, /mɨ́ːaŋ/) under Khmer suzerainty on the outskirts of the Khmer Empire, building the irrigation infrastructure and paddy fields for the wet-rice cultivation methods of the Tai people. Isan legends of Khun Burom (ขุนบูรม, ຂຸນບູຣົມ Khoun Bourôm, /kʰǔn bǔːlóm), shared with various Southwestern Tai peoples of Southeast Asia, Greater Assam and Yunnan, concerns the first ruler of Meuang Thaen (เมืองแถน, ເມືອງແຖນ Muang Thèn, /mɨ́ːaŋ tʰɛ̆ːn/) whose progeny go on to find the Tai dynasties that ruled over the various Tai mueang.[19]

As the Southwestern Tai-speaking peoples diverged, following paths down waterways, their dialects began to diverge into the various languages today, such as the Lao-Phuthai languages that developed along the Mekong River and includes Lao and its Isan sub-variety and the Chiang Saen languages which includes the Central Thai dialect that is the basis of Standard Thai. Despite their close relationship, there were several phonological divergences that drifted the languages apart with time such as the following examples:[20][21][22]

PSWT *ml > Lao /m/, > Thai /l/

• *mlɯn, 'slippery' > muen (มื่น, ມື່ນ mun, /mɨ̄ːn/), > luen (ลื่น, /lɯ̂ːn/)

PSWT *r (initial) > Laoː /m/, > Thai /r/

• *raːk, 'to vomit' > hak (ฮาก, ຮາກ, /hȃːk/), > rak (ราก, /râːk/)

PSWT *ɲ > Lao /ɲ/, > Thai /j/

• *ɲuŋ, 'mosquito' > yung (ยูง, ຍູງ gnoung, /ɲúːŋ/), > yung (ยุง, /juŋ/)

Similar influences and proximity allowed for both languages to converge in many aspects as well. Thai and Lao, although separated, passively influenced each other through centuries of proximity. For instance, the Proto-Southwestern Tai *mlɛːŋ has produced the expected Lao /m/ outcome maeng (แมง, ແມງ mèng, /mɛ́ːŋ/) and the expected Thai /l/ outcome laeng (แลง /lɛːŋ/), although this is only used in Royal Thai or restricted academic usage, with the common form malaeng (แมลง /maʔ lɛːŋ/), actually an archaic variant. In slang and relaxed speech, Thai also has maeng (แมง /mɛːŋ/), likely due to influence of Lao.[20]

Thai and Lao also share similar sources of loan words. Aside from many of the deeply embedded Sinitic loan words adopted at various points in the evolution of Southwestern Tai at the periphery of Chinese influence, the Tais in Southeast Asia encountered the Khmer. Khmer loan words dominate all areas and registers of both languages and many are shared between them. Khmer loan words include body parts, urban living, tools, administration and local plants. The Thai, and likely the Lao, were able to make Khmer-style coinages that were later exported back to Khmer.[23] The heavy imprint of Khmer is shown in the genetics of Tai speakers, with samples from Thai and Isan people of Lao descent showing proof of both the Tai migration but also intermarriage and assimilation of local populations. Scholars such as Khanittanan propose that the deep genetic and linguistic impact of the autochthonous Khmer and their language indicates that the earliest days of Ayutthaya had a largely bilingual population.[24] Although evidence and research in Lao is lacking, major Lao cities were known to have been built atop existing Khmer settlements, suggesting assimilation of the locals. Isan and Lao commonly use a Khmer loan not found in Thai, khanong (ขนง, ຂະໜົງ/ຂນົງ khanông, /kʰáʔ nŏŋ/), 'doorframe', from Khmer khnâng (ខ្នង, /knɑːŋ/), which means 'building', 'foundation' or 'dorsal ridge'.[23][25]

Indic languages also pushed Thai and Lao closer together, particularly Sanskrit and Pali loan words that they share. Many Sanskrit words were adopted via the Khmer language, particularly concerning Indian concepts of astrology, astronomy, ritual, science, kingship, art, music, dance and mythology. New words were historically coined from Sanskrit roots just as European languages, including English, share Greek and Latin roots used for these purposes, such as 'telephone' from Greek roots τῆλε tēle, 'distant' and φωνή phōnē which was introduced in Thai as thorasap (โทรศัพท์, /tʰoː raʔ sàp/) and spread to Isan as thorasap (โทรศัพท์, ໂທຣະສັບ/ໂທລະສັບ thôrasap, /tʰóː lāʔ sáp/) from Sanskrit dura (दूर, /d̪ura/), 'distant', and śabda (शब्द, /ʃabd̪a/), 'sound'. Indic influences also came via Pali, the liturgical language of Theravada Buddhism.

The effects of Khmer and Indic vocabulary did not effect all the Tai languages of Southeast Asia equally. The Tai Dam of northern Vietnam were shielded from the influence of the Khmer language and the Indic cultural influences that came with them and remain traditionally a non-Buddhist people. Although the Tai Dam language is a Chiang Saen language, albeit with a lexicon and phonology closer to Lao, the lack of Khmer, Sanskrit and Pali loan words makes the language unintelligible to Thai and Lao speakers.[26]

Wat Phra That Phanom in Nakhon Phanom. Built in the 16th century over earlier Khmer ruins when Isan was part of Lan Xang, the temple is an important place of pilgrimage, attracting Lao from Laos as well as Isan to its temple festivals.

Taking advantage of rapid decline in the Khmer Empire, Phra Chao Fa Ngoum (Northeastern Thai: ฟ้างุ้ม /fȁː ŋum/ RTGS Fa Ngum, cf. Lao: ຟ້າງູ່ມ) defeated the Khmer and united the Tai mueang of what is now Laos and Isan into the mandala kingdom of Lan Xang in 1354. Fa Ngoum was a grandson of the ruler of Muang Xoua (RTGS Mueang Sawa), modern-day Louang Phrabang. Lan Xang was powerful enough to thwart Siamese designs from their base at Sukhothai and later Ayutthaya.[27]

Khmer, and Sanskrit via Khmer, continued to influence the Lao language. Since Fa Ngoum was raised in the Khmer court, married to a Khmer princess and had numerous Khmer officials in his court, a now-extinct speech register known as rasasap (Northeastern Thai: ราซาศัพท์ /láː sáː sáp/, cf. Lao: ຣາຊາສັບ BGN/PCGN raxasap) was developed to address or discuss the king and high-ranking clergy. Khmer and Sanskrit also contributed many belles-lettres as well as numerous technical, academic and cultural vocabulary, thus differentiating the Lao language from the tribal Tai peoples, but pushing the language closer to Thai, which underwent a similar process. The end of the Lao monarchy in 1975 made the Lao raxasap obsolete, but as Thailand retains its monarchy, Thai rachasap is still active.[26]

The 16th century would see the establishment of many of the hallmarks of the contemporary Lao language. Scribed abandoned the use of written Khmer or Lao written in the Khmer alphabet, adopting a simplified, cursive form of the script known as Tai Noi that with a few modifications survives as the Lao script.[8] Lao literature was also given a major boost with the brief union of Lan Xang with Lan Na during the reign of Xay Xétthathirat (Northeastern Thai: ไซยเซษฐาธิราช /sáj sȅːt tʰăː tʰī lȃːt/, cf. Lao: ໄຊເສດຖາທິຣາດ) (1546–1551). The libraries of Chiang Mai were copied, introducing the tua tham (BGN/PCGN toua tham) or 'dharma letters' which was essentially the Mon-influenced script of Lan Na but was used in Lao specifically for religious literature.[8] The influence of the related Tai Lan Na language was strengthened after the capitulation of Lan Na to the Burmese, leading many courtiers and people to flee to safety to Lan Xang.

Lan Xang was religiously diverse, with most of the people practising Tai folk religion albeit somewhat influenced by local Austroasiatic animism, as well as the Brahmanism and Mahayana Buddhism introduced via the Khmer and Theravada Buddhism which had been adopted and spread by the Mon people. Although Lao belief is that the era of Lan Xang began the period of Theravada Buddhism for the Lao people, it was not until the mid-sixteenth century that the religion had become the dominant religion.[28]

The earliest and continuously used Theravada temple, Vat Vixoun was built in 1513 by King Vixounnarat (Northeastern Thai: วิชุลราช, Lao: ວິຊຸນນະຣາດ) (1500-1521). His successor, Phôthisarat (Northeastern Thai: โพธิสาลราช/โพธิสราช, Lao: ໂພທິສະຣາດ) (1520-1550), banned Tai folk religion and destroyed important animist shrines, diminished the role of the royal Brahmins and promoted Theravada Buddhism. Phôthisarat married a princess of Lan Na, increasing contact with the kingdom that had long adopted the religion via contacts with the Mon people, a process that would continue when Phôthisarat's son assumed the thrones of Lan Xang and Lan Na.[29]

With Theravada Buddhism came its liturgical language, Pali, an Indic language derived from the Prakrit Many Pali terms existed alongside earlier Sanskrit borrowings or were Sanskritised, leading to doublets such as Sanskrit maitri (Northeastern Thai: ไมตรี /máj tiː/, cf. Lao: ໄມຕີ/ໄມຕຣີ) and Pali metta (Northeastern Thai: เมตตา /mȇːt taː/, cf. Lao: ເມດຕາ/ເມຕຕາ), both of which signify 'loving kindness' although the Sanskrit term is more generally used for 'friendship'. The spread of Theravada Buddhism spread literacy, as monks served as teachers, teaching reading and writing as well other basic skills to village boys, and the Tai Noi script was used for personal letters, record-keeping and signage, as well as to record short stories and the klon (Northeastern Thai: กลอน /kɔːn/, cf. Lao: ກອນ BGN/PCGN kon) poetry that were often incorporated into traditional folksongs.[8]

Scene from Phra Lak Phra Ram, the Lao form of the Indian Ramayana. Several versions of the story were recorded on palm-leaf manuscripts between the 15th and early 19th centuries.[30] The story has been interwoven into Lao culture, music, song and theater and is still a part of Isan culture.

Lao literature was widely developed. Religious treatises and commentaries written on palm-leaf manuscripts (Northeastern Thai: ใบลาน (/baj láːn/), cf. Lao: ໃບລານ) were copied over and over, as the documents were hard to preserve in the hot and humid climate. In addition to religious treaties, many Lao folktales that were passed through song and stories were written down, many of which remain embedded in Isan culture today such as the following:[31]

• Nithan Khoun Bourôm (นิทานขุนบูรม /nī tʰáːn bǔː lóm]/ RTGS Nithan Khun Burom, cf. Lao: ຂຸນບູຣົມ)
• Sang Sinxay (Northeastern Thai: สังข์ศิลป์ไซย) /săŋ sĭn sáj/ RTGS Sang Sinsai, cf. Lao: ສັງສິນໄຊ)
• Phra Lak Phra Ram (Northeastern Thai: พระลักษมณ์พระราม) /pʰāʔ lāk pʰāʔ láːm/, cf. Lao: ພຣະລັກພຣະຣາມ)
• Thao Houng Thao Chuang (Northeastern Thai: ท้าวฮุ่งท้าวเจือง /tʰȃːo hūŋ tʰȃːo tɕɨaːŋ/, RTGS Thao Hung Thao Chueang, cf. Lao: ທ້າວຮຸ່ງທ້າວເຈືອງ)
• Phadaeng Nang Ai (Northeastern Thai: ผาแดงนางไอ่ /pʰăː dɛ̀ːŋ náːŋ āj/, cf. Lao: ຜາແດງນາງໄອ່ BGN/PCGN Phadèng Nang Ai)
• Phagna Khankhak (พญาคันคาก /pʰā ɲáː kʰán kʰȃːk/ RTGS Phaya Khankhak, cf. Lao: ພະຍາຄັນຄາກ)
• Vétsandon Xadôk (Northeastern Thai: เวสสันดรชาดก /ʋȇːt săn dɔːn sáː dók/ RTGS Wetsandon Sadok, cf. Lao: ເວດສັນດອນຊາດົກ)

Temple mural of Wat Photaram in Maha Sarakham Province. Dating to the reign of Siamese Ruler Rama III (1788-1851), the writing is in the Tai Noi script, an old form of the Lao alphabet. The Lao cities of the left bank were raided by Siamese soldiers and forced into the hinterlands of Siam, thus bringing the majority of the Lao people to the right bank.

Despite the long presence of Lan Xang and Lao settlements along the riverbanks, the Khorat Plateau remained depopulated since the Post-Angkor Period and a long series of droughts during 13th—15th centuries. The Lao settlements were found only along the banks of the Mekong River and in the wetter northern areas such as Nong Bua Lamphu, Loei, Nong Khai, with most of the population inhabiting the wetter left banks. This began to change when the golden age of Lao prosperity and cultural achievements under King Sourignavôngsa (สุริยวงศา Suriyawongsa, ສຸຣິຍະວົງສາ /sú lī ɲā ʋóŋ sǎː/) (1637-1694) ended with a successional dispute, with his grandsons, with Siamese intervention, carving out their separate kingdoms in 1707. From its ashes arose the kingdoms of Louang Phrabang, Vientiane and later in 1713, the Champasak. The arid hinterlands, deforested and depopulated after a series of droughts likely led to the collapse of the Khmer Empire, was only occupied by small groups of Austroasiatic peoples and scattered outposts of Lao mueang in the far north. In 1718, Mueang Suwannaphum (สุวรรณภูมิ, ສຸວັນນະພູມ Muang Suovannaphoum, /sú ʋán nāʔ pʰúːm) in 1718 in what is now Roi Et Province, was founded as an outpost of Champasak, establishing the first major Lao presence and the beginning of expansion of Lao settlement along the Si (ซิ, ຊີ /síː/) and Mun (มูล, ມູນ) rivers.

The bulk of the Lao, however, settled after 1778 when King Taksin, Siamese king during the Thonburi Period (1767—1782) conquered Champasak and Vientiane and raided Phuan areas for slaves, seizing the Emerald Buddha and Phra Bang (although the latter was eventually returned) and forcing some of the Lao across the river to settle in Isan. Louang Phrabang was spared most of the destruction by submitting to Siamese overlordship.[32] Although the kingdoms remained nominally autonomous, the Siamese demanded tribute and taxes, kept members of the respective royal houses as hostages to ensure loyalty and required the three Lao kings to come to the capital several times a year to hold audience with the Siamese king. When the kingdoms revolted, the Siamese armies retaliated by rounding up entire villages, tattooing them to mark them as slaves and forced to settle what is now Isan, forced to serve as soldiers or manpower in corvée projects to build roads, to grow food, build canals or serve as domestics. The greatest population transfer occurred after the Laotian Rebellion by Chao Anouvông (อนุวงศ์ Anuwong, Lao: ອານຸວົງ/ອານຸວົງສ໌, /ʔàː nū ʋóŋ/) in 1828 which led to the death of Anouvông and most of his family. The Siamese abducted nearly the entire population of Vientiane and its surrounding area and forced them to the right bank. Continued raids of people continued until the end of the nineteenth century.[33]

In addition to forced transfers, many Lao were encouraged, with some disillusioned princes granted lofty titles in exchange for loyalty and taxation, robbing the Lao kings of taxation and wealth as well as what little nominal authority they had left. This greatly expanded the Lao population of Isan and caused assimilation of the local peoples into the mix, a process which is occurring on a smaller scale even now. Siamese intervention paradoxically strengthened the Lao character of the region as the Siamese left the Lao areas alone as long as they continued to produce rice and continued to pay tribute. Direct Siamese rule did not extend past Nakhon Ratchasima, and the Lao mueang, whether paying their tribute directly to Bangkok or the remaining Lao kings and princes, were still nominally part of the separate kingdoms. Temples built in what is now Isan still featured the Tai Noi script on its murals and although Siam would intervene in some matters, daily administration was still left to the remaining kings and various Lao princes that served as governors of the larger mueang. The end result of the population movements re-centred the Lao world to the right bank, as today, if Isan and Lao speakers are counted together, Isan speakers form 80 per cent of the Lao-speaking population.[2][1]

Ratxadanay (ราซดนัย Ratchadanai, ຣາດຊະດະນັຍ, /lȃːt sāʔ dáʔ náj/) the last King of Champasak, which had been split in 1893 into a Thai- and French-controlled parts. In 1904, the implementation of the monthon system and the abolition of the monarchy by the French, ended the kingdom's existence.

After the French established their protectorate over the left bank Lao-speaking territories that became Laos during the conclusion of the Franco-Siamese War of 1893, the right bank was absorbed into Siam which was then ruled by King Wachirawut. To prevent further territorial concessions, the Siamese implemented a series of reforms that introduced Western concepts of statehood, administrative reforms and various measures to integrate the region which was until this point ruled as semi-autonomous out-lying territories nominally under the authority of the Lao kings. With the creation of provinces grouped into districts known as monthon (มณฑล, ມົນທົນ, /món tʰón/), the power of local Lao princes of the mueang in tax collection and administration were moved and replaced by crown-appointed governors from Bangkok which removed the official use of Lao written in Tai Noi in local administration. To achieve this, King Wachirawut had the help of his brother, Prince Damrongrachanuphap who recommended the system. The end of local autonomy and the presence of foreign troops led the Lao people to rebel under the influence of millennialist cult leaders or phu mi bun (ผู้มีบุญ, ຜູ້ມີບຸນ, /pʰȕː míː bun/) during the Holy Man's Rebellion (1901—1902), the last united Lao resistnce to Siamese rule, but the rebellion was brutally suppressed by Siamese troops and the reforms were fully implemented in the region shortly afterwards.[34][35][36]

Further reforms were implemented to assimilate and integrate the people of the 'Lao Monthon' into Siam. References to the 'Lao' and many cities and towns were renamed, such as the former districts Monthon Lao Gao and Monthon Lao Phuan which were renamed as 'Monthon Ubon' and 'Monthon Udon', respectively, shortly after their creation in 1912. Self-designation as Lao in the census was banned after 1907, with the Lao forced to declare themselves as Thai and speakers of a Thai dialect. The unofficial use of Lao to refer to them was discouraged, and the term 'Isan', originally just a name of the southern part of the 'Lao Monthon', was extended to the entire region, its primary ethnic group and language. The name change and replacement of the Lao language by Thai at the administrative level and reforms to implement Thai had very little effect as the region's large Lao population and isolation prevented quick implementation. Monks still taught young boys to read the Tai Noi script written on palm-leaf manuscripts since there were no schools, passages from old literature were often read during festivals and travelling troupes of mo lam and shaddow puppet performers relied on written manuscripts for the lyrics to poetry and old stories set to song and accompanied by the khaen alone or alongside other local instruments. Mountains, lack of roads, large areas without access to water during the dry season and flooding in the wet season continued to shield the Isan people and their language from direct Thai-language influence.[34][36]

A plaque in Laos, in Lao and English, commemorating the First Thai-Lao Friendship Bridge. The equivalent in Isan using Thai script is 'ขัวมิตรภาพ ไทย-ลาว'. The Lao signage read aloud would be perfectly understandable to Isan speakers, but since they were forced to abandon their shared writing system, Isan people cannot read it and suffer digraphia.

Suppression of the Isan language came with the 'Thai cultural mandates' and other reforms that aimed to elevate Central Thai culture and language, reverence to the monarchy and the symbols of state and complete integration into Thailand, known sa 'Thaification'. Most of these reforms were implemented by Plaek Phibunsongkhram, who changed the English name of Siam to 'Thailand' and whose ultra-nationalistic policies would mark Thailand during his rule from 1938 to 1944 and 1948–1957. These policies implemented an official diglossia. Isan was removed from public and official discourse to make way for Thai and the written language was banned, relegating Isan to an unwritten language of the home. Public schools, which finally were built in the region, focussed heavily on indoctrinating Isan people to revere the Thai monarchy, loyalty to the state and its symbols and mastery of the Thai language, with Isan treated as an inferior dialect. Pride in the language was erased as students were punished or humiliated for using the language in the classroom or writing in Tai Noi, planting the seed for future language shift as the region became bilingual.[36][34][37]

The old written language and the rich literature written in it were banned and was not discussed in schools. Numerous temples had their libraries seized and destroyed, replacing the old Lao religious texts, local histories, literature and poetry collections with Thai-script, Thai-centric manuscripts. The public schools also dismissed the old monks from their role as educators unless they complied with the new curriculum. This severed the Isan people from knowledge of their written language, shared literary history and ability to communicate via writing with the left bank Lao. In tandem with its removal from education and official contexts, the Thai language made a greater appearance in people's lives with the extension of the railroad to Ubon and Khon Kaen and with it the telegraph, radio and a larger number of Thai civil servants, teachers and government officials in the region that did not learn the local language.[38]

Words for new technologies and the political realities of belonging to the Thai state arrived from Thai, including words of English and Chinese (primarily Teochew) origin, as well as neologisms created from Sanskrit roots. Laos, still under French rule, turned to French, Vietnamese, repurposing of old Lao vocabulary as well as Sanskrit-derived coinages that were generally the same, although not always, as those that developed in Thai. For example, the word or aeroplane (UK)/airplane (US) in Isan was huea bin (Northeastern Thai: ເຮືອບິນ /hɨ́a bìn/) 'flying boat', but was generally replaced by Thai-influenced khrueang bin (Northeastern Thai: เครื่องบิน /kʰɨ̄aŋ bìn/) 'flying machine', whereas Lao retained hua bin (Lao: ເຮືອບິນ /hɨ́a bìn/) RTSG huea bin. Similarly, a game of billiards /bɪl jədz/ in Isan is (Northeastern Thai: บิลเลียด /bin lȋaːt/ from English via Thai; whereas on the left bank, people play biya (Lao: ບີຢາ /bìː jàː/) from French billard /bi jaʀ/. Despite this slow shift, the spoken language maintained its Lao features since most of the population was still engaged in agriculture, where Thai was not needed, thus many Isan people never mastered Thai fully even if they used it as a written language and understood it fine.[36][37]

The language shift to Thai and the increased influence of the Thai language really came to the fore in the 1960s due to several factors. Roads were finally built into the region, making Isan no longer unreachable for a much of the year, and the arrival of television with its popular news broadcasts and soap operas, penetrated into people's homes at this time. As lands new lands to clear for cultivation were no longer available, urbanisation began to occur, as well as the massive seasonal migration of Isan people to Bangkok during the dry season, taking advantage of the economic boom occurring in Thailand with increased western investment due to its more stable, non-communist government and openness.

The migrant workers from Isan filled the role of construction workers, taxi drivers, cleaners, vendors, dishwashers, domestics, sex workers and other menial professions, often settling in shanty towns on the outskirts of the city. The Isan people faced discrimination for their humble, Lao origins, funny accents, darker features and low-class professions but the extra money earned was sent to support family back home, and remittances such as these remain an important part of the Isan Region's GDP today. Having improved their Thai during these stints, the people returned to their villages, introducing the Bangkok slang words back home and peppering their speech with more and more Thai words.

Red Shirt political stage. Many Isan people joined the movement, protesting the ouster of PM Thaksin in 2006 and subsequent nullifications of candidates and parties attached to him.

The seasonal migrations were also spurned by the economic crash at the end of the Vietnam War, when large air bases were built in Isan and large numbers of US military stationed there provided a brief window of prosperity in the region. That period however exposed the Isan people to direct westernisation and adoption of more liberal social attitudes, helping foment a unique identity. Identification with 'Lao' identity became even more problematic, as the Isan people were always viewed as a fifth column ready to support their Lao brethren. Although the fear was exaggerated, members of the Lao Issara were able to find refuge in Isan during World War II, and communist supporters of the Pathét Lao often crossed and gained recruitments from the local Isan people.

Isan politicians tended to be mistrustful of Bangkok, believed in decentralisation of government and promoted strong development of regional economies and tended to be more leftist than the parties in power. Political repression of Isan included the assassination of political leaders in the 1930s and 1950s, the disrobement of monks in the 1970s critical of the government's role in the sangha and the return of military leaders. Crackdowns of political dissidents occurred throughout the 1960s, 1970s and 1980s until the threat of communism was diminished. The continued outlawing of parties supported by or purportedly funded by Thaksin Shinawatra, who was widely popular in Isan, was seen as continued affront to both democracy in Thailand and representation of Isan people in Thai politics, thus many Isan people were avid supporters of the Red Shirts.[39][40]

Around the 1990s, although the perceived political oppression continues and Thaification policies remain, attitudes towards regional languages relaxed. Academics at Isan universities began exploring the local language, history, culture and other folklore, publishing works that helped bring serious attention to preserving the Lao features of the language and landscape, albeit under an Isan banner. Students can participate in clubs that promote the local music, sung in the local Lao language, or local dances native to the area. Knowledge about the history of the region and its long neglect and abuse by Siamese authorities and resurrection of pride in local culture are coming to the fore, increasing expressions of 'Isan-ness' in the region. However, Thaification policies and the language shift to Thai continue unabated. Recognition of the Isan language as an important regional language of Thailand did not provide any funding for its preservation or maintenance other than a token of acknowledgement of its existence.[5][41]

A Thai road sign indicating a school ahead. As Isan has no official status, 'โฮงเฮียน' which is Isan for 'school' does not appear on signs.

The status of the Isan language is explained by Ethnologue as the 'de facto language of provincial identity' which 'is the language of identity for citizens of the province, but this is not mandated by law. Neither is it developed enough or known enough to function as the language of government business.' Although Thailand does recognise the existence of the Isan region as the primary regional language, this is a token gesture and does not elevate or promote the Isan language in any degree. In fact, the Thaification policies that removed Isan from the formal and public sphere and prevented Isan people from using the Tai Noi script are still active and mastery of Thai is required for participation in national life and economic and social advancement.

Unlike in Laos, where speakers make up only half the population and usually are found only in narrow bands hugging riparian valleys, the language is nevertheless official, used in all government and media and all registers of the language. Although Laos is bombarded with Thai media and many Lao speakers in Laos are also able to understand and read Thai, although some are unable to speak it and write it, the schools and government policy and the Lao people's desire to preserve their language have prevented the Thai relexification occurring in Isan.[42][43]

The spoken language is currently at Stage VIA, or 'vigorous', on the EGIDS scale developed by Joshua Fishman, which is defined by Ethnologue as a language that is used for 'face-to-face communication by all generations and the situation is sustainable'.[44] According to data from 1983, 88 percent of Isan households were predominantly Isan speaking, with 11 percent using both Thai and Isan at home, and only one percent using exclusively Thai.[2] Although this sounds promising for the continued future of the Isan language, there are many signs indicating that the language could reach Stage VIB, or 'threatened', which is defined as a 'language used for face-to-face communication within all generations, but it is losing users'. As a strong command of Thai is necessary for advancement in most government, academic, and professional realms, and in order to work in areas like Bangkok where Isan is not the local language.[5]

The language suffers from a negative perception and diglossia, so speakers have to limit their use of the language to comfortable, informal settings. Parents often view the language as a detriment to betterment of their children, who must master Standard Thai to advance in school or career paths outside of agriculture. The use of the Thai script, spelling cognate words in Isan as they are in Thai, also gives a false perception of the dialectal subordination of Isan and the errors of Isan pronunciation which deviate from Thai. As a result, a generational gap has arisen with old speakers using normative Lao and younger speakers using a very 'Thaified' version of Isan, increased code-switching or outright exclusive use of Thai. Many linguists and scholars of the Isan language believe that Thai relexification cannot be halted unless the script is returned, but this has little public or government support.[45][5]

Portions of an ancient legal text written in the Tai Noi script on a palm-leaf manuscript. The script was banned in the 1930s but survived in Laos as the modern Lao alphabet.

The written language is currently at Stage IX, which on the EGIDS scale is a 'language [that] serves as a reminder of heritage identity for an ethnic community, but no one has more than symbolic proficiency'.[44] This applies to both the Tai Noi script used for secular literature and the Tua Tham script previously used for Buddhist texts. Only a handful of people of very advanced age and caretakers of monasteries whose libraries were not destroyed during the Thaification implementation in the 1930s are able to read either script. Evidence for the use of the written language is hard to find, but well-worn murals of very old temples often have small bits of writing in the old script.[46]

In Laos, the orthography is a direct descendant of Tai Noi and continues its role as the official written language of the Lao language of the left bank as well as the script used to transcribe minority languages. The Lao written language has unified the dialects to some extant as well, as though the differences between dialects are sharper in Laos than Isan, one common writing system unites them.[43][46]

Until the 1980s, when the road infrastructure and more relaxed attitudes towards regional cultural awareness began to take root, it was common for Isan people to face severe prejudice and discrimination. Isan culture, although similar, was at the same time quite exotic, with the pungent foods and rural people referred to as 'stinky' and the people 'stupid' and 'lazy'. The isolated rural region continues to be Thailand's least educated, least urban, least developed and least integrated region of the country, which can be seen in the numbers. More than three-fourths of Isan's people are engaged in agriculture despite the challenges of floods, droughts and infertile soils but only generated 10.9 per cent of Thailand's gross domestic product in 2013. Isan culture and language immediately conjure up images of ignorant yokels, backwards traditionalists and country bumpkins.[47]

Beginning in the mid twentieth century, as new lands to develop were no longer available, Isan people began to migrate to Bangkok and other tourist areas or major cities to seek work during the dry season, when there was little activity on the farms, or permanently, sending occasional remittances to family members back home. Restricted by prejudice and lack of skills and education beyond farming, Isan people competed with migrant workers for jobs in construction crews, street sweepers, janitors, domestics, nannies, taxicab drivers, porters, shoeshine boys, vendors and the sex industry. Many establish residences on the outskirts of the city in unofficial shanty towns and urban slums. As a result of their rural roots and the ranks of Bangkok's urban poor, Isan people are often depicted as ignorant buffoons, naïve rural people, domestics in a Thai home or dimwitted, petty criminals.[45][48]

Acknowledgement of the unique history of the Isan language and the fact it is derived from a closely related albeit separate language is lacking, with the official and public position being that the language is a dialect of Thai. As a result of the great difference from Thai, based on tone, nasal vowels of a different quality and a special set of Lao vocabulary unfamiliar to Thai speakers, it is considered an 'inferior form of Thai' as opposed to its own separate language. The traditional avoidance of the language in the formal sphere re-enforces the superiority of Thai, which the Isan people have internalised to the point many do not have high opinions of their first language. Combined with vocabulary retentions, many of which sound oddly archaic or have become pejorative in Standard Thai, perpetuate the myth and negative perception of Isan as an uncouth language of rural poverty and hard agricultural life. Due to associations with Laos, the language was also viewed as a potential fifth column for Lao irredentism and the spread of communism into Thailand.[49] It was in the recent past quite common for Isan people to be corrected or ridiculed when they spoke because of their incomplete mastery of Standard Thai.[50]

In polling of language favorability amongst the general population of Thailand, the Isan language ranks last after Standard Thai and the primary Thai dialect of the other regions.[48] As a result of the need for Standard Thai proficiency in order to have better educational and employment prospects and avoid discrimination, anecdotal evidence suggests that more and more Isan children are being raised in the Thai language and are discouraged from using the local language at home.[50] The Thai language has already begun to displace the predominance of Isan in the major market towns, in part because they are often also administrative centres, and in some major cities, universities have attracted students from other regions.[49]

Since the late 1930s, Isan has been a bilingual area, with most people using Isan at home and in the village, but due to diglossia, switching to Thai for school, work and formal situations. Like all bilingual societies, Isan speakers often code-switch in and out of the Thai language. For example, in analysis of the eighty-eight volumes of the comic 'Hin the Mouse' in the city, the Thai language was used 62.91 per cent of the time to properly quote someone—such as someone that speaks Thai, 21.19 per cent of the time to provide further explanation and 8.61 per cent of the time to re-iterate a previous statement for clarification.[51] There are seven areas where the Thai language is employed, aside from direct quotation, such as the following: explanations, interjections, Thai culture, emphasis, re-iterations and jokes.[52]

Although some Isan people may not speak the language well, Thai is nevertheless a convenient language of clarification, especially between Isan speakers of different dialects that may be unfamiliar with local terms of the other speaker. As Isan does not exist in formal, technical, political or academic domains, it is generally more comfortable for Isan speakers to use Thai in these areas as a result of the diglossia, with many Isan speakers unaware or unfamiliar with native terms and belles-lettres that are still used in contemporary Lao. Thai is also sometimes used to avoid Isan features that are stigmatised in Thai, such as retention of vocabulary that is pejorative or archaic as well as Lao pronunciations of cognate words that sound 'folksy'. Despite the fact that code-switching is a natural phenomenon, younger generations are blurring the distinction between languages, using more Thai-like features and as they forget to switch back to Isan, language shift takes hold.[50][45]

Direct quotation

• หมูข้าน้อยเคยได้้้้้ยินครูเล็กบอกว่า ครูไม่ชอบฟังหมอรำ
• We have heard Teacher Lek tell us, 'Teacher does not like to listen to mo ram'.
• /mūː kʰȁː nɔ̑ːj kʰə́ːj dȃj ɲín kʰúː lēk bɔ̏ːk ʋāː kʰruː mâj tɕʰɔ̂ːp faŋ mɔ̌ː ram/
• mu khanoi khoei dai yin khru lek bok wa khru mai chop fang mo ram
• ໝູ່ຂ້ານ້ອຍເຄີຍໄດ້ຍິນຄູເລັກບອກວ່າ ครูไม่ชอบฟังหมอรำ

Explanations

• ข้อยออกล่วงเงินหน้าบ่ได้ดอก วันนี้ละก็ ผมไม่มีเงินนะครับ
• 'I cannot pay the money in advance, today, you know, I don't have money'.
• /kʰɔ̏ːj ʔɔ̏ːk ŋə́n lūːəŋ nȁː bɔ̄ː dȃj dɔ̏ːk wan níː laʔ kɔ̂ː pʰǒm mâj miː ŋɯn náʔ kʰráp/
• khoi ok luang ngoen na bo dai dok wan ni la ko phom mai mi ngoen na khrap
• ຂ້ອຍອອກເງິນລ່ວງຫນ້າເຂົາບໍ່ໄດ້ດອກ วันนี้ละก็ ผมไม่มีเงินนะครับ

Interjections

• อ้าย ไม่เป็นไรครับ เจ้าซิเฮ็ดดีที่สุดแด่
• 'Older brother, it's nothing at all. You will do your best'.
• /ʔâːj mâj pen raj kʰráp tɕâu sī hēt diː tʰīː sút dɛ̄ː/
• ai mai pen rai khrap chao si het di thisut dae
• ອ້າຍ ไม่เป็นไรครับ ເຈົ້າຊິເຮັດດີທີ່ສຸດແດ່

Culture

• กระยาหารกรุงเทพฯ โอชารสมากนะคะ เฮาควรไปฮอดกรุงเทพฯ นำกันเด้อ
• 'Bangkok fine cuisine is very delectable! We should go to Bangkok together'.
• /kràʔ yaː hǎːn kruŋ tʰêːp ʔoː tɕʰaː rót mâak náʔ kʰáʔ háo kʰúːən pài hɔ̑ːt kruŋ tʰêːp nám kan də̄ː/
• krayahan krung thep ocharot mak na kha hao khuan pai hot krung thep nam kan doe
• กระยาหารกรุงเทพฯ โอชารสมากนะคะ ເຮົາຄວນໄປຮອດ กรุงเทพฯ ນຳກັນເດີ໊

Re-iterations

• อี่พ่อ ผู้บ่าวพู้นมักกินน้ำซา แม่นอี่หลีเด้อ ผู้ชายนั่นชอบดื่มน้ำชาครับ
• 'Dad, that man over there likes to drink tea, it's true. That man over there likes to drink tea'.
• ʔīː pʰɔ̄ː pʰȕː bāːo pʰûːn māk kin nâm sáː mɛ̄ːn ʔīː lǐː də̄ː pʰûː tɕʰaj nân tɕʰɔ̂ːp dɯ`ːm nám tɕʰaː kʰráp/
• i pho phubao phun mak kin nam sa maen ili doe phuchai nan chop doem nam cha khrap
• ອີ່ພໍ່ ຜູ້ບ່າວພູ້ນມັກກິນນ້ຳຊາ ແມ່ນອີ່ຫຼີເດີ໊ ผู้ชายนั่นชอบดื่มน้ำชาครับ

Emphasis

• บ้านเราตลิ่งโขงฟากนี้เป็นของอาณาจักรไทยคะ ไทบ้านที่ฮิมของฟากพุ้นเป็นของเมืองลาวเด้อคะ
• Our village on this side of the Mekong's shore belong to the Kingdom of Thailand. The villagers along the banks on the other side of the Mekong belong to Laos.
• /bâːn rao taʔ lìŋ kʰǒːŋ fâːk níː pen kʰɔ̌ːŋ ʔaː naː jàk tʰaj kʰáʔ tʰáj bâːn tʰīː hím kʰɔ̆ːŋ fȃːk pʰûːn pen kʰɔ̆ːŋ mɨ́ːəŋ láːo də̄ː kʰáʔ/
• ban rao taling khong fak ni pen khong anachak thai kha thai ban thi him khong fak phun pen khong mueang lao doe kha
• บ้านเราตลิ่งโขงฟากนี้เป็นของอาณาจักรไทยคะ ບ້ານໄທທີ່ຮິມຂອງຟາກພູ້ນເປັນຂອງເມືອງລາວເດີ໊คะ

Jokes

• เจ้าเห็นไฟแดงบ่
  ไฟแดงเห็นครับ ไม่เห็นตำรวจ
• 'Did you see the red light?'
  'Yes, I saw the red light. I did not see the policeman'.
• /tɕâu hĕn fáj dɛːŋ bɔː/
  /faj dɛːŋ hěn kʰráp mâj hěn tam rùat/
• chao hen fai daeng bo
  fai daeng hen khrap mai hen tamruat
• ເຈົ້າເຫັນໄຟແດງບໍ່
  ไฟแดงเห็นครับ ไม่เห็นตำรวจ

The Thai language may not be the primary language of Isan, but nevertheless Isan people are in constant exposure to it. It is required to watch the ever popular soap operas, news and sports broadcasts or sing popular songs, most of it produced in Bangkok or at least in its accent. Thai is also needed as a written language for instructions, to read labels on packages, road signs, newspapers and books. Isan children who may struggle to acquire the language, nevertheless, are forced to learn the language as part of compulsory education and often when they are older, for employment. Although attitudes towards regional cultures and languages began to relax in the late 1980s, the legal and social pressures of Thaification and the need for Thai to participate in daily life and wider society continue. The influence of Thai aside, anecdotal evidence suggests that many older Isan lament the corruption of the spoken language spoken by younger generations and that the younger generations are no longer familiar with the traditional Lao forms used by previous generations.[45][53]

In a 2016 study of language shift, villagers in an Isan-speaking village were divided by age and asked to respond to various questionnaires to determine lexical usage of Lao terms, with those born prior to 1955, those born between 1965 and 1990 and those born after 1990. The results show what would be expected of a language undergoing language shift. As Isan and Thai already have a similar grammatical structure and syntax, the main variance is in lexical shift, essentially the replacement of Isan vocabulary. The oldest generation, at the time in their 60s or older, use very normative Lao features little different than those found in Laos. The middle generations, ranging from 35 to 50 years of age, had a greater prevalence of Thai vocabulary, but overall maintained a traditional Isan lexicon, with the Thai terms usually not the primary spoken forms. The youngest generation, although still arguably using very many Lao phrases and vocabulary, had a remarkable replacement of Isan vocabulary, with Thai forms becoming either the primary variant or replacing the Isan word altogether. Similarly, when Isan usage has two variants, generally a common one not understood in Thai and another that is usually a cognate, younger speakers tend to use the cognates with greater frequency, pushing their speech to Thai as older speakers will use them in variance.[54]

Thai loan words were generally localised in pronunciation, easing them into the flow of Isan conversation and unnoticeable to most but the oldest members of the community that preserve 'proper Isan' usage. Although the youngest generation was still speaking a distinct language, each generation brings the increased risk of the Isan language's extinction as it becomes relexified to the point of no longer being a separate language but a dialect of Thai with some Lao influence. The lack of official usage, official support for its maintenance and lack of language prestige hinder attempts to revitalise or strengthen the language against the advance of Thai.[53]

The development of 'Isan' identity and a resurgence in attention to the language has brought increased attention and study of the language. Academics at universities are now offering courses in the language and its grammar, conducting research into the old literature archives that were preserved. Digitising palm-leaf manuscripts and providing Thai-script transcription is being conducted as a way to both preserve the rapidly decaying documents and re-introduce them to the public. The language can be heard on national television during off-peak hours, when music videos featuring many Isan artists of molam and Isan adaptations of Central Thai luk thung music. In 2003, HRH Princess Royal Sirinthon was the patron of the Thai Youth Mo Lam Competition.[5]

Improved infrastructure and ease of travel restrictions between Thailand and Laos has allowed the continued movement of thousands of people every day, with people on either side crossing the river to visit relatives, shop, participate in religious festivals, conduct business or day-trip, with the Nong Khai-Vientiane Mukdahan-Savannakhét and Nakhon Phanom-Thakhèk border crossings particularly important due to the construction of bridges. Other major border crossings include Bueng Kan-Pakxan and the only non-Mekong checkpoint Chong Mek-Vangtao, although ferries cross the river in other areas. The familiarity of the language makes travel and business easy for Isan speakers, who are able to use their language freely in Laos and be understood.[4][5]

Isan shares its consonant inventory with the Lao language whence it derives. The plosive and affricate consonants can be further divided into three voice-onset times of voiced, tenuis and aspirated consonants. For example, Isan has the plosive set of voiced /b/, tenuis /p/ which is like the 'p' in 'spin' and aspirated /pʰ/ like the 'p' in 'puff'. Isan and Lao lack the sound /tɕʰ/ and its allophone /ʃ/ of Thai, replacing these sounds with /s/ in analogous environments. Similarly, /r/ is rare. Words in Isan and Lao cognate to Thai word with /r/ have either /h/ or /l/ in its place, although educated speakers in Isan or Laos may pronounce some words with /r/. In Thai, words with /r/ may be pronounced as /l/ in casual environments although this is frowned upon in formal or cultivated speech.

Unlike Thai, Isan and Lao have a /j/-/ɲ/ distinction, whereas cognate words from Isan and Lao with /ɲ/ are all /j/ in Thai. Substitution of /w/ with /ʋ/, which is not used in Thai, is common in large areas of both Laos and Isan but is not universal in either region, but is particularly associated with areas influenced by Vientiane and Central Lao dialects. The glottal stop occurs any time a word begins with a vowel, which is always built around a null consonant.

• ^1 Only used in Sanskrit or Pali loan words.
• ^2 Unique to Isan and Lao, does not occur in Thai but /ʋ/ is only an allophone of /w/ whereas /ɲ/ is phonemic.
• ^3 Thai spelling does not distinguish /j/ from /ɲ/.
• ^4 Lao ligature of silent /h/ (ຫ) or digraph; Thai digraph with silent /h/ (ห).
• ^5 Only as syllable-initial consonants.
• ^6 Use of /tɕʰ/ is Thai interference in Isan and rare in Laos, usually interference from a northern tribal Tai language, almost always /s/.
• ^7 Still taught as part of the alphabet, 'ฃ' and 'ฅ' are obsolete and have been replaced by 'ข' and 'ค', respectively.
• ^8 Mark of interference from Isan or erudition in Laos. Usually replaced by /l/ and even by 'ລ' /l/ in modern Lao writing.
• ^9 Used to mark /h/ in words that are etymologically /r/.
• ^10 All words that begin with vowels must be written with the anchor consonant and are pronounced with a glottal stop.
• ^11 Generally used in pre-1970s Lao.
• ^12 Only in very casual, informal Thai.

Consonant clusters are rare in Isan and Lao and were lost in pronunciation before the time writing in Tai Noi began, although some remnants of how words were spelt in the oldest documents suggest that some words may have retained them before the simplification process. As a result, in traditional Isan and Lao pronunciation, only /kw/ and /kʰw/ as consonant clusters. Due to a unique phonological process of diphthongisation, these clusters are lost when they occur before the vowels /aC/, /am/, /aː/ and /aːj/, limiting environments where these can occur. Thus the word for 'wide' is gwang (Northeastern Thai: กว้าง /kûːəŋ/, cf. Lao: ກວ້າງ BGN/PCGN kouang) and not the true cluster as occurs in Thai and is suggested by spelling, (Thai: กว้าง /kwâːŋ/). Isan speakers, however, spell words etymologically according to their Thai pronunciation if they are cognate words, thus Isan speakers write the clusters but traditionally do not pronounce them, although might in formal situations. In Laos, the pronunciation and spelling do not indicate the Thai clusters, and cognate words are spelled and pronounced without them, although a handful of Sanskrit and Khmer vocabulary may be pronounced in 'Thai' fashion by older, educated speakers of the Lao diaspora.

• ^1 Before /aC/, /aː/, /aːj/ and /am/ diphthongisation occurs which assimilates the /w/ so it is only a true cluster in other vowel environments, only occurs in Isan and Lao.

Isan shares with both Lao and Thai a restrictive set of permissible consonant sounds at the end of syllable or word. Isan, using its current method of writing according to Thai etymological spelling, preserves the spelling to imply the former sound of borrowed loan words even if the pronunciation has been assimilated. Due to spelling reforms in Laos, the letters that can end a word were restricted to a special set of letters, but older writers and those in the Lao diaspora occasionally use some of the more etymological spellings.

In pronunciation, all plosive sounds are unreleased, as a result there is no voicing of final consonants or any release of air. The finals /p/, /t/ and /k/ are thus actually pronounced /p̚/, /t̚/, and /k̚/, respectively.

• ^1 Where alternative spellings once existed, only these consonants can end words in modern Lao.
• ^2 Used in pre-1970s Lao spelling as word-final letters.
• ^3 Glottal stop is unwritten but is pronounced at the end of short vowels that occur at the end of a consonant.
• ^4 These occur only as parts of diph- or triphthongs and are usually included as parts of vowels.

The vowel structure of Isan is the same as the central and southern Lao dialects of Laos. The vowel quality is also similar to Thai, but differs in that the two back vowels, close back unrounded vowel /ɯ/ and the close-mid back unrounded vowel /ɤ/, centralised as the close central unrounded vowel /ɨ/ and the mid central vowel /ə/, respectively, as well as in diphthongs that may include these sounds. To Thai speakers, Isan and Lao vowels tend to have a nasal quality.

In many cases, especially diphthongs with /u/ as first element is lengthened in Isan as it is in Standard Lao, so that the word tua which means 'body' (Thai: ตัว, written the same in Isan) is pronounced /tua/ in Thai but in Isan as /tuːə/, similar to Lao: ຕົວ. The symbol '◌' indicates that required presence of a consonant, or for words that begin with a vowel sound, the 'null consonant' 'อ' or its Lao equivalent, 'ອ', which in words that begin with a vowel, represents the glottal stop /ʔ/. Short vowels that end with '◌ะ' or Lao '◌ະ' also end with a glottal stop.

Thai and Lao are both abugida scripts, so certain vowels are pronounced without being written, taking the form of /a/ in open syllables and /o/ in closed syllables, i.e., ending in a consonant. For example, the Khmer loan word phanom or 'hill' found in many place names in Isan is Northeastern Thai: พนม or 'PH-N-M' but pronounced /pʰāʔ nóm/, with 'PH' as the open syllable and 'N-M' as the closed syllable. In Lao orthography, inherited from Tai Noi, closed syllables are marked with a 'ົ' over the consonants and the /a/ of open syllables was unwritten, thus Lao: ພນົມ or 'Ph-N-^o-M'. In current practice as a result of spelling reforms, all vowels are written out and in modern Lao: ພະນົມ or 'Ph-a-N-^o-M' is more common thus modern Lao is no longer a true abugida.

Vowels usually exist in long-short pairs determined by vowel length which is phonemic, but vowel length is not indicated in the RTSG romanisation used in Thai or the BGN/PCGN French-based scheme commonly used in Laos. The Isan word romanised as khao can represent both Northeastern Thai: เขา /kʰăo/, 'he' or 'she', and Northeastern Thai: ขาว /kʰăːo/, 'white' which corresponds to Lao: ເຂົາ and Lao: ຂາວ, respectively, which are also romanised as khao. In these cases, the pairs of words have the same tone and pronunciation and are differentiated solely by vowel length.

• ^1 Unwritten in open syllables.
• ^2 Unwritten in closed syllables.

• ^1 Considered long vowels for the purpose of determining tone.
• ^2 Archaic usage common in pre-1970s Lao.
• ^3 The Thai vowel 'ำ' is a short vowel. In Isan, it is diphthongised after /w/ into /uːəm/.

• ^1 Considered long vowels for the purpose of determining tone.
• ^2 Archaic usage common in pre-1970s Lao.

As Isan is written in Thai, it also has the following symbols not found in the Lao script or its predecessor, Tai Noi. The letters are based on vocalic consonants used in Sanskrit, given the one-to-one letter correspondence of Thai to Sanskrit, although the last two letters are quite rare, as their equivalent Sanskrit sounds only occur in a few, ancient words and thus are functionally obsolete in Thai. The first symbol 'ฤ' is common in many Sanskrit and Pali words and 'ฤๅ' less so, but does occur as the primary spelling for the Thai adaptation of Sanskrit 'rishi' and treu (Thai: ตฤๅ /trɯː/ or /triː/), a very rare Khmer loan word for 'fish' only found in ancient poetry.

In the past, prior to the turn of the twentieth century, it was common for writers to substitute these letters in native vocabulary that contained similar sounds as a shorthand that was acceptable in writing at the time. For example, the conjunction 'or' (Thai: หรือ /rɯ́/ reu, cf. Lao: ຫຼຶ/ຫລື /lɨ̑ː/ lu) was often written Thai: ฤ such as in 'เขาไปบ้านแล้วหรือยัง' (Did he go home yet or not?) formerly written 'เขาไปบ้านแล้วฤยัง'. The practice had become obsolete by the time that Isan speakers began adopting Thai writing, but Isan speakers are likely exposed to it in school when studying Thai literature. These letters did not occur in Tai Noi or the modern Lao alphabet, and equivalent words of Sanskrit origin are spelled out with other letters. Isan speakers historically, and many still do, use the Lao pronunciation of these words.

• ^1 Archaic usage common in pre-1970s Lao.
• ^2 Archaic usage common in pre-1920s Thai.

• 
  Streets of Nong Khai, provincial capital of Nong Khai Province.
• 
  View of Vientiane from Si Chiang Mai District, Nong Khai, Thailand across the Mekong.
• 
  Lao woman in Vientiane selling herbs.

Vientiane Lao is the primary form of Isan spoken in the northern third of the region which was long settled since the days of Lan Xang and was ruled as part of the Kingdom of Vientiane, including most of Nong Khai, Nong Bua Lamphu, eastern Loei and portions of Saiyaphum and Bueng Kan. On the Laotian side, Vientiane Lao predominates in Vientiane City, the surrounding Vientiane Province and portions of Bolikhamxai and some areas of Xaisômboun.

As a result of the Lao rebellion of 1826 the Tai Wiang (ไทเวียง, ໄທວຽງ), /tʰáj ʋíːəŋ/), 'Vientiane people' of the city and surrounding parts of the kingdom, were rounded up by Siamese armies and forced to the right bank, greatly boosting the Lao population of what is now Isan. The Tai Wiang strengthened numbers in the northern third, where Vientiane Lao was traditionally spoken, but were scattered across the Isan region overall, with heavier concentrations in Yasothon, Khon Kaen and Hoi Et provinces. This likely had a levelling effect on the Lao language as spoken in Isan, as most Isan speakers regardless of speech variety are prone to using /ʋ/ as opposed to /w/ and the informal conversion of syllable-initial /k/ to /tɕ/ in relaxed, informal speech, which in Laos, is particularly characteristic of Vientiane speech. For example, the word kaem (แก้ม, ແກ້ມ kèm, /kɛ̂ːm/), 'cheek', is often pronounced *chaem (*แจ้ม, *ແຈ້ມ chèm, */tɕɛ̂ːm/).

In Laos, the speech of the old élite families was cultivated into Standard Lao as emulated by television and radio broadcasts from the capital as well as taught to foreign students of Lao, but the written language has been mainly based on Vientiane Lao for centuries after the capital of Lan Xang was moved in 1560. The speech of the Isan city of Nong Khai, which sits on the opposite bank of the Mekong, is almost indistinguishable in tone and accent from the speech of Vientiane.

• 
  Na Haew District, the westernmost region of Loei Province. Although most of the province speaks Vientiane Lao, some speakers of Northern Lao can be found in western Loei and in neighbouring Uttaradit Province.
• 
  Sisavang, penultimate King of Laos. As Louang Phrabang was the royal capital and home to the Laotian royal family, its members spoke a refined form of the local dialect.
• 
  A riverboat and marchers in the Lao New Year parade in Louang Phrabang.

Northern Lao is a very distinct dialect, exhibiting several features and lexical differences quite apart from other Lao dialects except Northeastern Lao (Phuan). Even though it borders the Vientiane Lao dialect region, there is a sharp boundary that divides them. The dialect shares many similarities with Tai Lanna and is classified accordingly as a Chiang Saen language by Ethnologue. The dialect is not common in Isan, restricted to western portions of Loei and pockets of villages spread throughout Udon Thani provinces. The Isan people of Phitsanulok and Uttaradit provinces, particularly the narrow strip hugging the shore of the Mekong and bordering Loei, outside of Isan are generally speakers of Northern Lao. In Laos, it is the primary dialect spoken in Louang Phrabang and Xaignabouli provinces. In the other northern Laotian provinces of Oudômxai, Houaphan, Louang Namtha and Phôngsali, native Lao speakers are a small minority in the major market towns but Northern Lao, highly influenced by the local languages, is spoken as the lingua franca across ethnic groups of the area.[55]

Northern Lao, specifically the speech of the city of Louang Phrabang was originally the prestigious variety of the language with the city serving as the capital of Lan Xang for the first half of its existence, with the kings of the city made kings of all of Laos by the French. Although the language lost its prestige to Vientiane Lao, Northern Lao is important for its history, as many of the earliest Lao literary works were composed in the dialect, and it served, in a refined form, as the royal speech of the Laotian kings until 1975 when the monarchy was abolished. Louang Phrabang remains the largest city in the northern region of Laos, serving as an important centre of trade and communication with the surrounding areas.

Despite proximity to speakers of Vientiane Lao, Northern Lao is quite distinct. Unlike other Lao dialects with six tones, Northern Lao speakers use only five. Due to the distinctive high-pitch, high-falling tone on words with live syllables starting with low-class consonants, the dialect is said to sound softer, sweeter and more effeminate than other Lao dialects, likely aided by the slower speed of speaking.[59] Similar in tonal structure and quality to Tai Lanna, likely facilitated by the immigration of Lanna people to Louang Phrabang after Chiang Mai's fall to the Burmese in 1551, the dialect is classified apart from other Lao dialects as Chiang Saen language by Ethnologue.[2] Northern Lao also resisted the merger of Proto-Tai */aɰ/ and */aj/ that occurred in all other Lao dialects, except Northeastern Lao. This effects the twenty or so words represented by Thai 'ใ◌' and Lao 'ໃ◌', which preserve /aɰ/ in Northern Lao. This vowel has become /aj/, similar to Thai 'ไ◌' and Lao 'ໄ◌' which is also /aj/. Northern Lao also contains numerous terms not familiar to other Lao speakers.[60]

• 
  Chiang Khan in Loei Province, Thailand. The town and surrounding district has a large Phuan minority.
• 
  A rural road in Xiangkhouang Province. This was the original Phuan homeland and Phuan is the primary Tai language of the province.
• 
  Young Phuan women in traditional clothing.

The Phuan (พวน, ພວນ Phouan, /pʰúːən/) are a tribal Tai people originally inhabiting Xiangkhouang and parts of Houaphan provinces of Laos. As a result of slave raids and forced population transfers, there are small, scattered villages of Phuan in Sakon and Udon Thani provinces and another area around Bueang Kan, Nong Khai and Loei provinces in Thailand. Despite the small numbers and isolation, the Siamese kept the Phuan apart from the Lao, and in from other Thai people in Northern and Central Thailand were small communities of Phuan also exist, forcing them to live apart and dress in black clothing. The Phuan in turn practised endogamous marriage habits and steadfastness to their language and culture. It is distinct enough that Thais and Isan people generally consider it distinct, although Phuan is considered a Lao dialect in Laos. As a Tai language of northern Southeast Asia, it shares many similarities with Tai Dam and Tai Lan Na. In contrat to other minority languages of Isan, it is not losing ground to the Thai or Isan language in Isan.[2]

Similar to Northern Lao, Phuan has maintained the Proto-Southwestern Tai distinction of Proto-Tai */aɰ/ and */aj/, but the outcome is /əː/ and /aj/, respectively, similar to the Northern Lao dialects of Houaphan which has a significant Phuan presence. Similar to the Phuthai (ผู้ไท, ຜູ້ໄທ Phou Tai, /pʰȕː tʰáj/), final /k/ has been replaced by the glottal stop /ʔ/. What mainly distinguishes Phuan from all other Lao dialects are the vowel transformations that distinguish cognates, such as Lao /uːə/ appearing as Phuan /oː/ and Lao /ɨːə/ appearing as Phuan /iə/. This and a very distinct vocabulary make Phuan mutually intelligible but with difficulty to other Isan or Lao speakers and even harder to understand for native speakers of Central Thai. Outside of Xiangkhouang and other native areas in Laos, the scattered Phuan settlements in Thailand have been greatly influenced by the tones of the local languages, however even though most maintain six, those in Louang Phrabang or Central Thailand only have five and when spoken as a second language by tribal peoples of various languages, they may use seven, however all Phuan dialects share distinct tonal split, with syllables beginning with low-clas consonants and marked with the mai ek (may ék) tone mark pronounced differently than similar situations with other class consonants. This is also done in some varieties of Western Lao. Most other Lao dialects have the same tone when marked with the mai ek tone mark.[62]

• 
  Isan tuk-tuk drivers awaiting passengers in Nakhon Phanom.
• 
  View of Thakhèk from the banks of the Mekong in Nakhon Phanom.
• 
  Lao people at the Souk Somboun Market. Thakhèk, Khammouan Province, Laos.

Central Lao represents a transitional variety, with northern varieties closer to Vientiane Lao and southern varieties, roughly sough of the confluence of the Xé Noi river with the Mekong, the speech varieties begin to approach Southern Lao. Some linguists, such as Hartmann, place Vientiane Lao and Central Lao together as a singular dialect region.[63] More Vientiane-like speech predominates in the Isan provinces of Bueng Kan, Sakon Nakhon, most of Nakhon Phanom and some areas of Nong Khai provinces and on the Laotian side, portions of eastern and southern Bolikhamxai and Khammouan provinces. More Southern Lao features are found in the speech of Mukdahan and southern Nakhon Phanom provinces of Thailand and Savannakhét Province of Laos.

Nevertheless, the tones of the southern Central varieties, such as spoken in Mukdahan, Thailand and Savannakhét, Laos have a tonal structure more akin to Vientiane Lao, sharing certain splits and contours. These areas do, however, exhibit some Southern features of their lexicon, such as the common use of se (เซ, ເຊ xé, /sêː/), 'river', which is typical of Southern Lao as opposed to nam (น้ำ, ນ້ຳ, /nȃm/), which is the more common word and also signifies 'water' in general. Mukdahan-Savannakhét area speakers also understand mae thao (แม่เฒ่า, ແມ່ເຖົ້າ, /mɛ́ː tʰȁo/) as a respectful term for an 'old lady' (as opposed to Vientiane 'mother-in-law') and use pen sang (เป็นสัง, ເປັນສັງ, /pȅn sȁŋ/) instead of Vientiane pen yang (เป็นหยัง, ເປັນຫຍັງ, /pen ɲăŋ/), 'what's wrong?', as is typical of Southern Lao.

• 
  Isan people buying and selling goods the night market in Ubon Ratsathani.
• 
  Entrance to Chongmek, Thailand from Vangtao, Laos at the only terrestrial border crossing between Ubon and Champasak provinces.
• 
  Lao family on a 'Chinese water buffalo' in Champasak Province.

Southern Lao is spoken along the southern third of Isan and Laos. This region covers the Thai provinces of Surin, Buriram and Sisaket, where a large minority of speakers are Khmer people speaking the archaic northern variety of Khmer and another Austroasiatic peoples, the Kuy people, use Southern Lao as a second language to engage with their Isan neighbours. It is also spoken in Ubon Ratsathani, Amnat Charoen and portions of Yasothon and Nakhon Ratsasima. In Laos, it is the primary dialect of Champasak, Salavan, Attapeu and Xékong provinces. There are also small pockets of speakers located in Steung Treng Province, Cambodia or Siang Taeng (เซียงแตง, ຊຽງແຕງ, /síaːŋ tɛːŋ/), particularly near the Mekong River close to the Laotian border. Many of the areas where Southern Lao is spoken were formerly part of the Kingdom of Champasak, one of the three successor states to the Kingdom of Lan Xang, prior to the division of the Lao-speaking world between France and Siam.

Compared to other Isan and Lao dialects, Southern Lao has low tones in syllables that begin with high- or middle-class consonants and have long vowels. High- and middle-class consonants marked with the mai to tone mark are low and low-falling, respectively, but in these cases are pronounced with a very strong glottalisation, which can be described as 'creaky'. Combined with the somewhat faster manner of speaking and reduced tendency to soften consonants at the end of words, Southern Lao sounds very rough and harsh to speakers of other dialects. Many of these features, such as the faster speaking pace and glottalisation may be influences from Austroasiatic languages as most of the region was inhabited by the Khmer, Kuy and various other Austroasiatic peoples until the eighteenth century when the Lao began to settle and even now, Khmer speakers comprise half the population of Surin and roughly a quarter each of the populations of Sisaket and Buriram provinces.[65]

Specific dialectal words include don (ดอน, ດອນ, /dɔ̀ːn/), 'riparian island', se (เซ, ເຊ xé, /sȅː/)) and many of the words used in Savannakhét that are more typical of Southern Lao such as mae thao (แม่เฒ่า, ແມ່ເຖົ້າ, /mɛ́ː tʰȁo/) as a respectful term for an 'old lady' (as opposed to Vientiane 'mother-in-law') and use pen sang (เป็นสัง, ເປັນສັງ, /pȅn sȁŋ/) instead of Vientiane pen yang (เป็นหยัง, ເປັນຫຍັງ pén gnang, /pen ɲăŋ/), 'what's wrong?'. Possibly as a result of historical Khmer influence and current influences from Thai, Southern dialects tend to pronounce some words with initial Proto-Southwestern Tai */r/ as a either the rhotic tap /ɾ/ or a strongly velarised /ɬ/ which is confused with /d/ by speakers of other Lao dialects which have /h/, for example Vientiane Lao hap (ฮับ, ຮັບ, /hāp/), 'to receive', and honghaem (โฮงแฮม, ໂຮງແຮມ hônghèm, /hóːŋ hɛ́ːm/) are pronounced as lap (หรับ, ລັບ, /ɾàp/) and honglaem (โฮงแลม, ໂຮງແລມ hônglèm, /hɔ̏ːŋ ɾɛ̏ːm/), respectively but it may sound like *dap and *hongdaem (hông dèm) to other Lao but is really strongly velerasied /ɬ/ or a rhotic tap /ɾ/.[66] Southerners also tend to use chak (จัก, ຈັກ, /tɕa᷇k/) to mean 'to know someone' as opposed to hu chak (ฮู้จาก, ຮູ້ຈັກ hou chak, /hȗː tɕák/) used in all other dialects.

• 
  Isan woman approaching a coffee vendor in Kalasin.
• 
  Rice maturing in the paddy in rural Maha Sarakham Province.
• 
  Main road in Roi Et.

Western Lao does not occur in Laos but is the primary dialect of Kalasin, Hoi Et and Maha Sarakham, but it is also spoken in much of Saiyaphum and portions of Nakhon Ratsasima.

• Central Thai (Thai Klang), is the sole official and national language of Thailand, spoken by about 20 million (2006).
• Northern Thai (Phasa Nuea, Lanna, Kam Mueang, or Thai Yuan), spoken by about 6 million (1983) in the formerly independent kingdom of Lanna (Chiang Mai). Shares strong similarities with Lao to the point that in the past the Siamese Thais referred to it as Lao.
• Southern Thai (Thai Tai, Pak Tai, or Dambro), spoken by about 4.5 million (2006)
• Phu Thai, spoken by about half a million around Nakhon Phanom Province, and 300,000 more in Laos and Vietnam (2006).
• Phuan, spoken by 200,000 in central Thailand and Isan, and 100,000 more in northern Laos (2006).
• Shan (Thai Luang, Tai Long, Thai Yai), spoken by about 100,000 in north-west Thailand along the border with the Shan States of Burma, and by 3.2 million in Burma (2006).
• Lü (Lue, Yong, Dai), spoken by about 1,000,000 in northern Thailand, and 600,000 more in Sipsong Panna of China, Burma, and Laos (1981–2000).
• Nyaw language, spoken by 50,000 in Nakhon Phanom Province, Sakhon Nakhon Province, Udon Thani Province of Northeast Thailand (1990).
• Song, spoken by about 30,000 in central and northern Thailand (2000).

The consonants of the old Tai Noy alphabet. Letter shapes have been preserved, with few changes, in the modern Lao alphabet.

The original writing system was the Akson Tai Noi (Northeastern Thai: อักษรไทน้อย /ák sɔ̆ːn tʰáj nɔ̑ːj/, cf. Lao: ອັກສອນໄທນ້ອຽ BGN/PCGN Akson Tai Noy), 'Little Tai alphabet' or To Lao (Northeastern Thai: โตลาว /to: láːo/, cf. Lao: ໂຕລາວ), which in contemporary Isan and Lao would be Tua Lao (Northeastern Thai: ตัวลาว /tuːa láːo/ and Lao: ຕົວລາວ, respectively, or 'Lao letters.' In Laos, the script is referred to in academic settings as the Akson Lao Deum (Lao: ອັກສອນລາວເດີມ /ák sɔ̆ːn láːo d̀ɤːm/, cf. Northeastern Thai: อักษรลาวเดิม RTGS Akson Lao Doem) or 'Original Lao script.' The contemporary Lao script is a direct descendant and has preserved the basic letter shapes. The similarity between the modern Thai alphabet and the old and new Lao alphabets is because both scripts derived from a common ancestral Tai script of what is now northern Thailand which was an adaptation of the Khmer script, rounded by the influence of the Mon script, all of which are descendants of the Pallava script of southern India.[46]

'Sri Ubon Rattanaram Museum' written in English and Isan in the Tai Noi script. This would be rendered as Northeastern Thai: พิพิธภัณฑ์ศรีอุบลรัตนาราม in the Thai script, identical to how it is in the Thai language, and Lao: ພິພິດທະພັນສີອຸບົນຣັດຕະນາຣາມ in the contemporary Lao.

The Tai Noi script was the secular script used for personal letters, record keeping, signage, songs, poems, stories, recipes, medical texts and religious literature aimed at the laity. The earliest evidence of the script in what is now Thailand is an inscription at Prathat Si Bunrueang in Nong Bua Lamphu dated to 1510, and the last epigraphic evidence is dated to 1840 AD, although large numbers of texts were destroyed or did not survive the heat and humidity. The use of the script was banned in 1871 by royal decree, followed by reforms that imposed Thai as the administrative language of the region in 1898, but these edicts had little impact as education was done informally by village monks. The written language survived to some degree until the imposition of the radical Thaification policies of the 1930s, as the Central Thai culture was elevated as the national standard and all expressions of regional and minority culture were brutally suppressed.[49] Many documents were confiscated and burned, religious literature was replaced by royally sanctioned Thai versions and schools, where only the Thai spoken and written language was used, were built in the region. As a result, only a handful of people, such as academic experts, monks that maintain the temple libraries and some elderly people of advanced age are familiar with and can read material written in Tai Noi script. This has led to Isan being mainly a spoken language, and when it is written, if at all, it is written in the Thai script and spelling conventions that distance it from its Lao origins.[46]

Signage in Isan written in the Tai Noi script was installed throughout Khon Kaen University in 2013. Students were surveyed after the signs were put up, and most had a favorable reaction to the signage, as over 73 per cent had no knowledge of a previous writing system prior to the forced adoption of the Thai language and alphabet. Lack of a writing system has been cited as a reason for the lack of prestige speakers have for the language, disassociation from their history and culture and for the constant inroads and influence of the Thai language. Revival of the written language, however, is hampered by lack of support. Despite the easement of restrictions and prejudice against Isan people and their language, the Thaification policies that suppressed the written language remain the law of the land in Thailand today. Although contemporary Lao people from Laos can read Tai Noi material with only a little difficulty, Isan speakers are generally unfamiliar with the Lao script due to lack of exposure.[5][44]

• *ຊຳບາຍດີບໍ່ (ສະບາຍດີບໍ່), สบายดีไหม, 'how are you?'
• ມາແຕ່ໃສນໍ, มาจากไหนเหรอ, 'where did it come from?
• ກິນເຂົ້າສວຍກັບຫຍັງນໍ, กินข้าวเช้ากับอะไรเหรอ, 'what did you eat with breakfast?'
• ຊ່ອຍຂ້ອຍແນ່, ช่วยฉันด้วย, 'help me!'
• ແຂ້ວໂກນ, ฝันผุจนเป็นหลุม, 'rotten tooth cavity'
• ເມືອເຮືອນ, กลับบ้าน, 'to return home'
• ມ້ຽນມັດອັດຮີ, เก็บกวาดให้เรียบร้อย, 'clean up after it's done'
• ອ່ວຍໜ້າມາພີ້ หันหนามาทางนี้, 'come this way'

Screenshot of a karaoke VCD from molam singer, Chintara Phunlap. In the Lao script, the lyrics seen would appear as 'ໜີໄປບວດໃຫ້ມັນແລ້ວສາບໍ້'.

The ban on the Tai Noi script in the 1930s led to the adoption of writing in Thai with the Thai script. Very quickly, the Isan people adopted an ad hoc system of using Thai to record the spoken language, using etymological spelling for cognate words but spelling Lao words not found in Thai, and with no known Khmer or Indic etymology, similarly to as they would be in the Lao script. This system remains in informal use today, often seen in letters, text messages, social media posts, lyrics to songs in the Isan language, transcription of Isan dialogue and personal notes.

There are two aspects of Lao phonology inherited in Isan that native speakers will substitute different letters to represent the proper sound.

Proto-Southwestern Tai initial /r/ > /h/

• Lao 'ຣ' /r/ and 'ຮ' /h/
• Isan 'ร' /r/ and 'ฮ' /h/
• Thai ron (ร้อน /rɔ́ːn/), 'hot' > Isan hon (ฮ้อน, ຮ້ອນ, /hɔ̑ːn/)

Loss of Proto-Southwestern Tai /tɕʰ/ by merger with /s/ in Lao

• Lao 'ຊ' /s/, romanised as 'x'
• Isan 'ซ' /s/ replaces Thai 'ช' /tɕʰ/
• Thai chang (ช้าง, /tɕʰáːŋ/), 'elephant' > Isan sang (ซ้าง, ຊ້າງ xang, /sȃːŋ/)

Although it is not universal, Isan speakers may also employ the rare tone marks to record idiosyncratic or to record the accent of a speaker, in regards to tone since most Lao dialects have six instead of five tones, although the shapes of the tone contours and the rules between varieties are distinct from each other and Thai.

Special tone marks

• Thai krai (ใคร, /kʰraj/), 'who' > Isan phudai (ผู้ใด, ຜູ້ໃດ phoudai, /pʰȕː daj/)
• Isan form with tone mark phudai (ผู้ใด๋, *ຜູ້ໃດ໋)

The Thai script and etymological Thai spelling is detrimental on several fronts. For those that wish to learn the Isan language, it makes the language look like Thai with some strange words as it does not record the unique sounds of the Isan language that are not distinguished in Thai. Isan tonal patterns are markedly distinct from Thai, but the Thai script is taught according to Thai tone rules, leading Thai speakers to mispronounce the tones of a native speaker. The deviations and similarity to Thai make it appear that Isan is a rural dialect instead of its own language with a separate history.[53]

No orthographical distinction of /ɲ/ and /j/

• Lao 'ຍ' /ɲ/ and 'ຢ' /j/
• Lao gnam (ຍາມ, /ɲáːm/), 'to guard', cf. Isan [n]yam (ยาม, /ɲáːm/)
• Lao yam (ຢາມ, /jaːm/), 'to visit', cf. Isan yam (ยาม, /jaːm/)

Incomplete representation of /tɕʰ/ > /s/

• Lao 'ສ' /s/ and 'ຊ' /s/
• Isan 'ฉ' /s/ and 'ฌ' /s/ (but represent /tɕʰ/ as in Thai)
• Thai chabap (ฉบับ, /tɕʰaʔ bàp/), 'copy' > Isan chabap (ฉบับ, ສະບັບ, /sáʔ báp/)
• Thai chan (ฌาน, /tɕʰaːn/), 'meditation' > Isan chan (ฌาน, ຊານ, /sáːn/)

Substitution of Thai spellings and suppression of non-Thai forms

• Thai len (เล่น, /lên/), 'to play' or 'to amuse oneself' > (Written) Isan len (เล่น, */lēːn/)
• Traditional Isan spellings lin (หลิ้น, ຫຼິ້ນ/ຫລິ້ນ, /lȉn/) or variant len (เหล้น, ເຫຼ້ນ/ເຫລັ້ນ, /lȅn/)
• Thai lot (ลด, /lót/, 'to lower', 'to diminish' > Isan lot (ลด, ລົດ lôt, /lōt/)
• More common Isan variant lut (หลุด, ຫຼຸດ/ຫລຸດ lout, /lút/)

Consonant clusters that do not exist in Lao

• Lao katiem, phèng and khong
• Thai kratiem (กระเทียม, /kraʔ tʰiam/), 'garlic' vs. Isan krathiem (กระเทียม, ກະທຽມ, /káʔ tʰíːəm/) (pronounced as if spelt kathiam *กะเทียม)
• Thai phleng (เพลง, /pʰleːŋ/), 'song' > Isan phleng (เพลง, ເພງ, /pʰéːŋ/) (pronounced as if spelt pheng *เพง)
• Thai khlong (คลอง, /kʰlɔːŋ/), 'canal' > Isan khlong (คลอง, ຄອງ khong, /kʰɔ́ːŋ/) (pronounced as if spelt khong *คอง)

Etymological spelling of Sanskrit loan words vs. Lao phonetical spelling

• Sanskrit śalya (शल्य, /ʃalya/), 'surgeon' + vaidhya (वैद्य, /ʋaid̪ʱja/), 'doctor'
• Thai sanlayaphaet (ศัลยแพทย์ /sǎn yaʔ pʰɛ̂ːt/) or sanyaphaet (ศัลยแพทย์, /sǎn láʔ yáʔ pʰɛ̂ːt/), spelling suggests 'salyaphaetya' > Isan sanlayaphaet (ศัลยแพทย์, ສັນລະຍະແພດ sanlagnaphèt, /săn lāʔ ɲāʔ pʰɛ̑ːt/) or sunyaphaet (ศัลยแพทย์, ສັນຍະແພດ sangnaphèt, /sǎn ɲāʔ pʰɛ̂ːt/)
• Sanskrit Nārāyaṇa (नारायण, /naːraːjaɳa/)
• Thai Narai (นารายณ์, /naː raːj/), 'Narayana', spelling suggests *Nārāyna > Isan Narai (นารายณ์, ນາຣາຽ/ນາລາຍ, /naː laːj/)

An example of the Tai Tham alphabet formerly used in Laos and Isan for religious literature.

The Tai Tham script (Northeastern Thai: อักษรไทธรรม /ák sɔ̆ːn tʰáj / RTGS akson Tai Tham, cf. Lao: ອັກສອນໄທທັມ) were also historically known simply as tua tham (Northeastern Thai: ตัวธรรม /tùa tʰám/, cf. Lao: ຕົວທຳ/ຕົວທັມ BGN/PCGN toua tham) or 'dharma letters'. The script is the same as used to write Tai Lanna (Kham Mueang), Tai Lue, Tai Khoen and shares similarities with the Burmese script, all of which are ultimately derived from the Old Mon script. Tai Tham was introduced during the reign of Setthathirath who although a prince of Lan Xang, was first crowned king of Lan Na. The dynastic union allowed easy movement of monks from Lan Xang that came to copy the temple libraries to bring back home.[69]

Although both the ancient forms of the Mon and Khmer script are different, they are both abugidas that descend from the Brahmic scripts introduced via contacts with South Indian traders, soldiers, merchants and Brahmans. As a Mon-derived script, Tai Tham has many similarities with the writing systems for Burmese, Shan, Rakhine and modern Mon and rounder letter forms compared to the angled letters of Khmer.[69] Letters can be stacked, sometimes with special subscript forms, similar to 'ຼ' which was used in Tai Noi and also in modern Lao as the subscript version of 'ຣ' /r/ or 'ລ' /l/ as in Lao: ຫຼວງພຼະບາງ/ຫລວງພຣະບາງ. Letters also are more circular or rouded than the typically angled style of Khmer.[70]

As the name suggests, its use in Lao was restricted to religious literature, either used to transcribe Pali, or religious treatises written in Lao intended solely for the clergy. Religious instructional materials and prayer books dedicated to the laity were written in Tai Noi instead. As a result, only a few people outside the temples were literate in the script. In Isan, evidence of the script includes two stone inscriptions, such as the one housed at Wat Tham Suwannakhuha in Nong Bua Lamphu, dated to 1564, and another from Wat Mahaphon in Maha Sarakham from the same period.[70] Most of the script is recorded on palm-leaf manuscripts, many of which were destroyed during the 'Thaification' purges of the 1930s; contemporaneously this period of Thai nationalisation also ended its use as the primary written language in Northern Thailand.[69]

Although no longer in use in Isan, the alphabet is enjoying a resurgence in Northern Thailand, and is still used as the primary written script for the Tai Lü and Tai Khün languages spoken in the 'Golden Triange' where Thailand, Laos, Burma and southern China meet. Its use is rather limited to the long-term monks in Laos and most materials published today are in the modern Lao script.[69]

Inscription in the Khom script (Ancient Khmer script). This Khmer script, distinct from the devised script for secret messages of Ong Kommandam during the Holy Man's Rebellion, was used to write Buddhist, Brahmanic and ritual texts.

The Khom script (อักษรขอม /kʰɔ̆ːm/, cf. Lao ອັກສອນຂອມ, Aksone Khom) was not generally used to write the ancient Lao language of Isan, but was often used to write Pali texts, or Brahmanic rituals often introduced via the Khmer culture. Khom is the ancient Tai word for the Khmer people, who once populated and ruled much of the area before Tai migration and the assimilation of the local people to Tai languages. The modern Khmer alphabet is its descendant. It was generally not used to write the Lao language per se, but was often found in temple inscriptions, used in texts that preserve Brahmanic mantras and ceremonies, local mantras adopted for use in Tai animistic religion and other things usually concerned with Buddhism, Brahmanism or black magic, such as yantras and sakyan tattoos.

Also known by the same name is an obscure script that was invented for conveying secret messages that could not be deciphered by the French or Siamese forces that had divided Laos by Ong Kommandam, who had taken over as leader after the death of Ong Kèo during the Holy Man's Rebellion. As Ong Kommandam and many of his closest followers were speakers of Bahnaric languages spoken in southern Laos, most of the known texts in the language were written in Alak—Ong Kommandam's native language—and the Bahnaric Loven languages of Juk, Su' and Jru', and some in Lao.[71]

Although the shapes of the letters have a superficial resemblance to several writing systems in the area, it was not related to any of them. It enjoys some usage as a language of black magic and secrecy today, but only a handful of people are familiar with it. Although the word Khom originally referred to the Khmer, it was later applied to related Austroasiatic peoples such as the Lao Theung, many of which had supported Ong Kammandam.[71]

Many Isan (and Lao) terms are very similar to words that are profane, vulgar or insulting in the Thai language, features which are much deprecated. Isan uses อี่ (/ʔīː/, cf. Lao: ອີ່) and อ้าย (/ʔâːj/, cf. Lao: ອ້າຍ/archaic ອ້າຽ), to refer to young girls and slightly older boys, respectively. In Thai, the similarly sounding อี, i (/ʔiː/) and ไอ้, ai (/ʔâj) are often prefixed before a woman's or man's name, respectively, or alone or in phrases which are considered extremely vulgar and insulting. This taboo expressions such as อีตัว "i tua", "whore" (/ʔiː nɔːŋ/) and ไอ้บ้า, "ai ba", "son of a bitch" (/ʔâj baː/).

In Isan and Lao, these prefixes are used in innocent ways as it does not carry the same connotation, even though they share these insults with Thai. In Isan, it is quite common to refer to a young girl named 'Nok' as I Nok (อี่นก, cf. Lao ອີ່ນົກ I Nôk or to address one's mother and father as i mae (อี่แม่, cf. Lao ອີ່ແມ່ I Mae, /ʔīː mɛ̄ː/) and I Pho (อี่พ่อ, cf. Lao ອີ່ພໍ່ i pho, /ʔīː pʰɔ̄ː/), respectively. Of course, as Thai only uses there cognate prefixes in fairly negative words and expressions, the sound of Isan i mae would cause some embarrassment in certain situations. The low status of the language is contributing to the language shift currently taking place among younger Isan people, and some Isan children are unable to speak the language fluently, but the need for Thai will not diminish as it is mandatory for education and career advancement.[45]

Isan has maintained the phonological inventory of the Lao language, so any differences in the phonology between Thai and Lao also apply to spoken Isan. Thai and Lao share a similar phonology, being closely related languages, however, several developments occurred in Lao that clearly distinguish them. Tone, including patterns and quality, is the largest contributing factor and vary widely between varieties of Lao or Isan, but together they share splits quite distinct to Standard Thai and other Central Thai speech varieties. There are also several key sound changes that occurred in the Lao language that differentiate it from Thai. As Isan is written according to Thai spelling rules in the Thai script, these changes are not recorded in Isan written in Thai script except for a small number of cases.

Isan noticeably lacks the /r/ of formal Thai, replacing it with /h/ or /l/, as well as /t͡ɕʰ/ which is replaced by /s/. Isan also has the consonant sounds /ɲ/ and /ʋ/ which are absent in Thai. Aside from these differences, the consonantal inventory is mostly shared between the two languages.

Unlike Thai, the only consonant clusters that traditionally occur is C/w/, limited in Isan and Lao to /kw/ and /kʰw/ but only in certain environments as the /w/ is assimilated into a diphthongisation process before the vowels /aː/, /am/, /aːj/ and /a/ thus limiting their occurrence. For example, Isan kwang (กว้าง, ກວ້າງ kouang, /kûːəŋ/) is pronounced *kuang (*กว้ง, *ກວ້ງ) but kwaen as in kwaen ban (แกว้นบ้าน, ແກວ່ນບ້ານ khoèn ban, /kwɛ̄ːn bȃːn/), 'to feel at home', has a vowel that does not trigger the diphthongisation. The consonant clusters of Proto-Tai had mostly merged in Proto-Southwestern Tai, but clusters were re-introduced with Khmer, Sanskrit, Pali and European loan words, particularly C/l/ and C/r/. Lao simplified the clusters to the first element, but sporadically maintained its orthographic representation as late as the early twentieth century although their pronunciation was simplified much earlier. This was likely an influence of Thai.[74]

In some instances, some loan words are sometimes pronounced with clusters by very erudite speakers in formal contexts or in the speech of Isan youth that is very Thaified, otherwise the simplified pronunciation is more common. Lao speakers, especially erudite speakers may write and pronounce prôkram (ໂປຣກຣາມ, /proːkraːm/), via French programme (/pʁɔgʁam/), and maitri (ໄມຕຣີ, /máj triː/) from Sanskrit maitri (मैत्री, /maj triː/) are common, more often than not, they exist as pôkam (ໂປກາມ, /poːkaːm/) and maiti (ໄມຕີ, /máj tiː/), respectively. Similarly, Isan speakers always write and sometimes pronounce, in 'Thai fashion', maitri (ไมตรี, /máj triː/) and prokraem (โปรแกรม, /proː krɛːm/), via English 'programme' or 'program' (US), but most speakers reduce it to máj tiː/ and /poː kɛːm/, respectively, in normal speech.

Proto-Southwestern Tai initial voiced alveolar trill /r/ remained /r/ in Thai, although it is sometimes pronounced /l/ in informal environments, whereas Lao changed the sound to the voiceless glottal fricative /h/ in these environments. The sound change likely occurred in the mid-sixteenth century as the Tai Noi orthography after that period has the letter Lao letter 'ຮ' /h/ which was a variant of 'ຣ' /r/ used to record the sound change. Isan speakers employing the Thai script will substitute the Thai letter 'ฮ' /h/, generally only used in loan words, mainly Chinese dialect loan words and more recent European and other borrowings, to record where /h/ appears in place of 'ร' /r/. This /h/ is distinct from Lao 'ຫ' /h/ and analogous Thai 'ห' /h/ in etymology. The change also included numerous small words of Khmer origin such as hian (เฮียน, ຮຽນ, /híːən/), 'to learn', which is rian (เรียน, /riːən/) in Thai, from Khmer riĕn (រៀន, /riən/).

The shift of Proto-Southwestern Tai */r/ to /h/ in Lao was inconsistent, with some factors that prevented the transition. Instead, these situations led to the shift of /r/ to the alveolar lateral approximant /l/, similar as to what occurs in informal, casual Thai. Polysyllabic loan words from Khmer as well as Indic sources such as Khmer and Pali may have seemed too 'foreign' compared to the monosyllabic loan words which may have been regarded as native, somewhat similar to English 'beef', ultimately from French boeuf but fully anglicised in spelling and pronunciation, versus more evidently French loan words such as crème anglaise, which retains a more French-like pronunciation. Thai speakers sometimes use /l/ in place of /r/ in relaxed, basilectal varieties but this is deprecated in formal speech.

• rasa (ราซา, ຣາຊາ raxa, /láː sáː/) from Sanskrit rājā (राजा, /raːdʒaː/), 'king', cf. Thai racha (ราชา, /raː tɕʰaː/), 'king'
• raka (ราคา, ລາຄາ, /láː kʰáː/}}), 'price' from Sanskrit rāka (राक, /raːka/), 'wealth', cf. Thai raka (ราคา, /raː kʰaː/)
• charoen (เจริญ, ຈະເລີນ chaluen, /tɕáʔ lə́ːn/), 'prosperity', from Khmer camraeum (ចំរើន, /tɕɑm raən/), cf. Thai charoen (เจริญ, /tɕaʔ rɤːn/)
• rabam (ระบำ, ລະບຳ, /lāʔ bam/, 'traditional dance', from Khmer rôbam (របាំ, /rɔ bam/), cf. Thai rabam (ระบำ, /rabam/)

Lao and Thai both have digraphs, or in the case of Lao ligatures, that consist of a silent /h/ that was historically pronounced at some ancient stage of both languages, but now serves as a mark of tone, shifting the sound to a high-class consonant for figuring out tone. The /h/ may have prevented the assimilation of these words to /h/, as these end up as /l/ in Lao. Similarly, this may have also prevented /r/ to /h/ in Khmer loan words where it begins the second syllable.

• rue (หรือ, ຫຼື/ຫລື lu, /lɨ̑ː/) versus rue (หรือ, /rɯ̌ː/), 'or' (conjunction)
• lio (หลี่ว, ຫຼີ່ວ/ຫລີ່ວ, /līːw/ versus ri (หรี่, /rìː/), 'to squint' (one's eyes)
• kamlai (กำไร, ກຳໄລ, /kam láj/), 'profit', from Khmer kâmrai (កំរៃ, /kɑm ray/), cf. Thai kamrai (กำไร, /kam raj/)
• samrap (สำหรับ, ສຳລັບ samlap, /săm lāp/), 'for' (the purpose of, to be used as, intended as), from Khmer sâmrap (សំរាប់, /sɑmrap/), cf. Thai samrap (สำหรับ, /sǎm ráp/)

There are a handful of words where the expected conversion to /h/ did not take place, thus yielding /l/. In some cases, even in the Lao of Laos, this can be seen as historic Siamese influence, but it also may have been conservative retentions of /r/ in some words that resisted this change. For example, Isan has both hap (ฮับ, ຮັບ, /hāp/) and lap (รับ, ລັບ, /lāp/), both of which mean 'to receive' and are cognates to Thai rap (รับ, /ráp/), and the lap variety in Isan and parts of Laos, especially the south, may be due to Thai contact. In other cases, it is because the words are recent loans from Thai or other languages. In Isan, younger speakers often use /l/ in place of /h/ due to language shift.

• ro (รอ, ລໍ, /lɔ́ː/), 'to wait, to wait for', cf. Thai ro (รอ, /rɔː/)
• rot (รถ, ຣົຖ/ລົດ/ລົຖ/ lôt, /lōt/), 'car' or 'vehicle', cf. Thai rot (รถ, /rót/)
• lam (ลำ, ລຳ, /lám/), 'to dance', cf. Thai ram (รำ, /ram/)
• rom (โรม, ໂຣມ/ໂລມ rôm, /lóːm/), 'Rome', cf. Thai rom (โรม, /roːm/)
• rangkai (ร่างกาย, /lāːŋ kaːj/) (Isan youth), traditionally hangkai (hāːŋ kaːj, ຮ່າງກາຽ, /hāːŋ kaːj/), 'body' (anatomic), cf. Thai rangkai (ร่างกาย, /râːŋ kaːj/)

Proto-Tai */ɟ/ and */ʑ/ had merged into Proto-Southwestern Tai */ɟ/, which developed into /tɕʰ/ in Thai, represented by the Thai letter 'ช'. Only a small handful of Proto-Tai words with */č/ were retained in Proto-Southwestern Tai, represented by the Tai letter 'ฉ', but this also developed into /tɕʰ/ in Thai and most words with 'ฉ' are either Khmer, Sanskrit or more recent loan words from Chinese dialects, particularly Teochew (Chaoshan Min). Thai also uses the letter 'ฌ' which only occurs in a handful of Sanskrit and Pali loan words where it represented /ɟʱ/, but in Thai has the pronunciation /tɕʰ/. Lao has developed /s/ where Thai has /tɕʰ/, with the letter 'ຊ' /s/, but romanised as 'x', is used to represent cognate words with Thai 'ช' or 'ฌ' whereas Thai 'ฉ' is replaced by Lao 'ສ' /s/ in analogous environments.

Isan speakers will sometimes substitute the Thai letter 'ซ' /s/ in place of Thai 'ช' /tɕʰ/ in cognate words, but this is never done to replace 'ฌ' /tɕʰ/ and sometimes avoided in formal, technical or academic word of Khmer, Sanskrit and Pali origins even if the pronunciation is still /s/, although educated Isan speakers and Isan youth may you use /tɕʰ/ due to code-switching or language shift. Similarly, the letter 'ฉ' /tɕʰ/ is usually retained even if it is better approximated by tone and phonology by 'ส' /s/ as is done in similar environments in Lao.

• ^1 Proto-Tai etymon.
• ^2 Pre-1975 Lao spelling.

Lao retains a distinction with some words retaining a voiced palatal nasal /ɲ/ from the merger Proto-Southwestern Tai */ɲ/ and */ʰɲ/ and some words with /j/ derived from the merger of Proto-Southwestern Tai */j/ and */ˀj/. The change may have persisted into Thai after the adoption of writing, as some words provide clues to their etymology. For example, Proto-Southwestern Tai */ɲ/ and */ʰɲ/ correspond to the Thai spellings 'ญ' and 'หญ' whereas */j/ and */ˀj/ correspond to Thai spellings 'ย' and 'อย', respectively, all of which have merged in pronunciation to /j/ in Thai, although as this pronunciation was likely lost shortly after literacy, not all Thai words have this corresponding spelling. Thai also uses the letter 'ญ' in words of Khmer, Sanskrit and Pali where the source language has /ɲ/ but these words now have /j/ pronunciation.

Lao maintains the distinction with the letters 'ຍ' /ɲ/ and 'ຢ' /j/, but /j/ is a rarer outcome in Lao and most instances of Thai 'ย' and 'ญ' or digraphs 'หย' and 'หญ' will result in Lao 'ຍ' /ɲ/ or 'ຫຽ/ຫຍ' /ɲ/. With a few exceptions, only Proto-Southwestern Tai */ˀj/ yields /j/. Lao, unlike Thai, has also adopted Khmer, Sanskrit and Pali loan words and retains the /ɲ/ pronunciation of the loan source languages, but has also converted the consonantal /j/ into /ɲ/ in borrowings. The Lao letter 'ຍ' also represents /j/, but only in diphthongs and triphthongs as a final element. As the Lao language of Isan is written in Thai according to Thai spelling rules, the phonemic distinction between /j/ into /ɲ/ cannot be made in the orthography, thus Isan speakers write ya 'ยา' which suggests ya (ยา, /jaː/), 'medicine' but is also used for [n]ya (ยา, ຍາ, /ɲáː/), an honoroary prefix used to address a person who is same in age as one's grandparents. These are distinguished in Lao orthography, but Isan speakers either use context or a tone mark, as they differ in tone, to differentiate the words.

• ^1 Proto-Southwestern Tai etymon.
• ^2 Pre-1975 alternate Lao spelling.

The Proto-Southwestern Tai cluster *ml was simplified, producing an expected result of /l/ in Thai and /m/ in Lao. The Saek language, a Northern Tai language distantly related to Thai and Lao preserves these clusters. For instance, Proto-Southwestern Tai *mlɯn, 'to open the eyes', is mlong in Saek (มลอง, ມຼອງ, /mlɔːŋ/) but appears as luem (ลืม, /lɯm/) and muen (มืน, ມືນ mun, /mɨ́ːn/) in Isan and Lao.[75]

Lao speakers generally pronounce cognates of Thai with initial /w/ as the voiced labiodental approximant /ʋ/, similar to a faint 'v', enough so that the French chose 'v' to transcribe the Lao letter 'ວ' /ʋ/. The letter is related to Thai 'ว' /w/. The sound /ʋ/ is particularly noticeable in the Vientiane and Central Lao dialects, with a strong pronunciation favoured by the élite of Vientiane. In Isan, the rapid but forced resettlement of the people of Vientiane and surrounding areas to the right bank greatly boosted the Lao population, but likely led to some dialect levelling, which may explain the prevalence of /ʋ/ throughout the region, regardless of personal Isan dialect.

The replacement is not universal, especially in Laos, but a shift towards /w/ is also occurring in Isan due to the persistent pressures of the Thai language since the sound /ʋ/ is considered provincial, being different from Thai, as opposed to Laos where it is the prestigious pronunciation. Due to the difference in pronunciation, the French-based system used in Laos uses 'v' whereas the English-based Thai system of romanisation uses 'w', so the Lao city of Savannakhét would be rendered 'Sawannakhet' if using the Thai transcription.

Another influence of the massive migration of the people of Vientiane to the right bank is the common tendency to replace the voiceless velar plosive /k/ with the voiceless alveolo-palatal affricate /t͡ɕ/. For instance, the people of the city of Khon Chaen, more generally referred to as Khon Kaen (ขอนแก่น, ຂອນແກ່ນ Khon Kèn, /kʰɔ̆ːn kɛ̄ːn/) in formal contexts, refer to their city as Khon Chaen (ขอนแจ่น, *ຂອນແຈ່ນ, /kʰɔ̆ːn t͡ɕɛ̄ːn/) in more relaxed settings. In Laos, this is particularly an informal feature specific to Vientiane Lao but is not used in the official written and spoken standard as it is an informal variant, whereas in Isan, it is commonly used but deprecated as a regional mispronunciation. It is also limited to certain words and environments.

Lao innovated a diphthongisation that assimilates the /w/ in instances of /kw/ and /kʰw/ in certain environments. This is triggered by the vowels /a/, /aː/, /aːj/ and /am/, but the cluster is retained in all other instances. The /w/ is converted to /uː/ and the vowel is shortened to /ə/. This is not shown in the orthography, as it must have evolved after the adoption of writing in the fourteenth century. Cognate words in Lao or Isan where this diphthongisation occurs have no alteration in spelling from Thai counterparts. For example, the Thai word for 'to sweep' is kwat (กวาด, /kwàːt/) but is kwat (กวาด, ກວາດ kouat, /kȕːət/) and has the suggested pronunciation /kwȁːt/ but is pronounced *kuat (*กวด, *ກວດ kouat). The counterpart of Thai khwaen (แขวน, kʰwɛ̌ːn), 'to hang' (something) is also khwaen (แขวน, ແຂວນ khwèn, /kʰwɛ̆ːn/) since the vowel /ɛː/ does not trigger diphthongisation.

The vowels /a/, /aː/, /aːj/ and /am/ correspond to Thai '◌ั◌', '◌า', '◌าย' and '◌ำ' and the Lao '◌ັ◌', '◌າ', '◌າຽ/◌າຍ' and '◌ຳ'. The clusters that can undergo this transformation are /kw/, Thai 'กว' and Lao 'ກວ' or /kw/, Thai 'ขว' and 'คว and Lao 'ຂວ' and 'ຄວ'. The non-diphthongised pronunciations as used in Thai are also used by some Isan speakers as a result of Thai influence. In Laos, non-diphthongisation is not incorrect, but may sound like a Thai-influenced hypercorrection or very pedantic. As it is the normal pronunciation in Laos and Isan, it limits the instances of consonant clusters that are permissible.

The Thai diphthongs and triphthongs with the component /ua/ undergo a lengthening of the /u/ to /uː/ and shortens the /a/ to /ə/, although the shortened diphthong can sound like /uː/ to Thai speakers. In Thai, this includes the vowels /ua/ represented medially by '◌ว◌' and finally by '◌ัว', /uaʔ/ by '◌ัวะ' and the final triphthong /uaj/ by '◌วย'. Lao has /uːə/ represented medially by '◌ວ◌' and finally by '◌ົວ', /uːəʔ/ by '◌ົວະ' and the final triphthong /uːəj/ by '◌ວຽ/◌ວຍ'.

For example, the Thai word tua (ตัว, /tua/, used as the classifier for animals, letters as well as general word to mean 'creature' is instead tua (ตัว, ຕົວ, /tuːə/) in Isan. To Thai speakers who may not perceive the weak schwa /ə/ may hear tu (ตู, /tuː/), an archaic first-person pronoun no longer used or used in pejorative fashion. This may have been another innovation, like C/w/ diphthongisation, that occurred after the adoption of writing as it is not represented orthographically.

The close back unrounded vowel /ɯ/ is centralised to the close central unrounded vowel /ɨ/ in Lao which is not found in Thai. This also applies to all variants of /ɯ/ that occur in Thai, i.e., all cognates with instances of Thai /ɯ/ are Lao /ɨ/, including diphthongs and tripthongs that feature this vowel element. Some very traditional dialects of Southern Lao and the Phuan dialect front the vowel all the way to /iː/.

The close-mid back unrounded vowel /ɤ/ is centralised to the close-mid central unrounded vowel /ɘ/ in Lao. Similar to the conversion of /ɯ/ to /ɨ/, it also effects all instances in diphthongs as well.

Abugida scripts traditionally do not notate all vowels, especially the short vowel /a/, usually realised as /aʔ/ in Thai and Lao phonology. This especially effect the polysyllabic loan words of Sanskrit, Pali or Khmer derivation. Instances of when or when not to pronounce a vowel have to be learned individually as the presence of the vowel is inconsistent. For example, the Sanskrit word dharma (धर्म, /d̪ʱarma/) which can mean 'dharma', 'moral' or 'justice', was borrowed into Thai as simply tham (ธรรม /tʰam). As a root, it appears as simply tham as in thamkaset (ธรรมเกษตร /tʰam kàʔ sèːt/) 'land of justice' or 'righteous land' with the /aʔ/ or thammanit (ธรรมนิตย์ /tʰam máʔ nít/), 'moral person' with /aʔ/. This is not always justified by etymology, as the terms derive from Sanskrit dharmakṣetra (धर्मक्षेत्र, /d̪ʱarmakʂetra/)—actually signifies 'pious man' in Sanskrit—and dharmanitya (धर्मनित्य, /d̪ʱarmanit̪ja/), respectively, both of which feature a pronounced but unwritten /a/. Lao and most Isan speakers in relaxed environments will pronouce the 'extra' vowel yielding *thammakaset (ธรรมเกษตร, ທັມມະກເສດ/ທັມມະກເສດຣ໌/ທຳມະກະເສດ thammakasét, /tʰám māʔ ká sȅːt/) and thammanit (ธรรมนิตย์, ທັມມະນິດ/ທັມມະນິຕຍ໌/ທຳມະນິດ, /tʰám māʔ nīt/). There are also instances where Thai has the epenthetic vowel lost in Lao, such as krommathan (กรมธรรม์, /krom maʔ tʰan/), 'debt contract', whereas Lao has nativised the pronunciation to kromtham (กรมธรรม, ກົມທັນ/ກົມທໍາ kômtham, //kòm tʰám/). This is an exception, as the extra vowel is a sign of Lao-retained pronunciation such as Thai chit (จิตร, /jìt/), 'paiting' from Sanskrit citra (चित्र, /t͡ʃit̪ra/) which is chit (จิตร, ຈິຕຣ໌/ຈິດ, /t͡ɕít/), chit[ta] (จิตร, ຈິດຕະ chitta, /t͡ɕít táʔ/) or extremely epentheticised chit[tara] (จิตร, ຈິດຕະຣະ/ຈິດຕະລະ chittala, /t͡ɕít táʔ lā/ in Isan.

Although it may seem like a minor difference, it is akin to the stigmatised mispronunciations of the English words 'athlete' (/ˈæθ liːt/) and 'arthritis' (/ɑː θə ˈraɪ tɪs/, US /ɑːɹθ ˈraɪ tɪs/) as *'athelete' (*/ˈæθ ə liːt/) or *'arthuritis' (*{{IPA|/ɑː θə ˈraɪ tɪs/, US /ɑːɹ θəɹ ˈraɪ tɪs/), respectively. As another feature of Isan that deviates from Thai, it is deprecated. Few Isan people are aware that the stigmatised pronuncitions are actully the 'proper' Isan form inherited from Lao. Many of these loan words are limited to academic and formal contexts which usually trigger code-switching to forml Thai, thus Isan speakers may pronounce these words more akin to Thai fashion although to varying degrees of adaptation to Isan pronunciation. Lao speakers also tend to insert epenthetic vowels in normal speech, as opposed to standard Thai where this is less common, thus 'softening' the sentence and making dialogue less stacatto. For instance, the Isan phrase chak noi (จักน้อย, ຈັກນ້ຽ/ຈັກນ້ອຽ/ຈັກນ້ອຍ /tɕʰák nɔ̑ːj/) which means 'in just a bit' is often pronounced chak-ka noy (*จักกะน้อย /*tɕʰák káʔ nɔ̑ːj/, cf. Lao *ຈັກກະນ້ອຍ) but this may be perceived as 'slurred' speech to Thai speakers.

• ^1 Basilectal Isan pronunciation based on historic Lao usage.
• ^2 'Lao-ified' pronunciation influenced by formal Thai.
• ^3 Hypercorrection amongst the educated to approximate Sanskrit pronunciation.

'Mekong River'

• Thai แม่โขง Maekhong /mɛˆː kʰǒːŋ/ and Isan แม่โขง /mɛ̄ː kʰɔːŋ/, 'AE-M O-KH-NG'
• Isan pronounced as *แม่ของ
• Lao ແມ່ຂອງ Mèkhong /mɛ̄ː kʰɔːŋ/ 'AE-M KH-O-NG'

'Chaiburi' (Thai name of the Lao province of Xaignabouli)

• Thai ไชยบุรี Chaiburi /tɕʰaj bù riː/ and Isan ไซยบุรี /sáj ɲāʔ bú līː/, 'AI-CH-Y-B-_U-R-^I'
• Isan pronounced as *ไซยะบุรี
• Archaic Lao ໄຊຍບຸຣິ 'AI-X-GN-B-_U-R-^I' and modern Lao ໄຊຍະບູລີ Xaignabouri/Xaignabouli 'AI-X-GN-A-B-_U-L-^II' /sáj ɲāʔ bú līː/

'Hanuman'

• Thai หนุมาน Hanuman /hàʔ nú maːn/ 'H-N-_U-M-AN' and Isan /หุลมาน/หุนละมาน Hunlaman /hŭn lāʔ máːn/ 'H-_U-L-M-A-N'/'H-_U-N-L-A-M-A-N'
• Archaic Lao ຫຸລມານ 'H-_U-L-M-A-N' and modern Lao ຫຸນລະມານ 'H-_U-N-L-A-M-A-N', /hŭn lāʔ máːn/
• But also Isan หนุมาน Hanuman 'H-N-_U-M-A-N' and Lao ຫະນຸມານ Hanouman 'H-A-N-_U-M-A-N'

Even Thai words with clear cognates in Lao and Isan can differ remarkably by tone. Determining the tone of a word by spelling is complicated. Every consonant falls into a category of high, middle or low class. Then, one must determine whether the syllable has a long or a short syllable and whether it ends in a sonorant or plosive consonant and, if there are any, whatever tone marks may move the tone.[76] Thai กา ka, crow, has a middle tone in Thai, as it contains a mid-class consonant with a long vowel that does not end in a plosive. In Standard Lao, the same environments produce a low-rising tone /kàː/ but is typically /kâː/ or rising-mid-falling in Western Lao.

Despite the differences in pattern, the orthography used to write words is nearly the same in Thai and Lao, even using the same tone marks in most places, so it is knowing the spoken language and how it maps out to the rules of the written language that determine the tone. However, as the Tai languages are tonal languages, with tone being an important phonemic feature, spoken Lao or Isan words out of context, even if they are cognate, may sound closer to Thai words of different meaning. Thai คา kha /kʰaː/, 'to stick' is cognate to Isan คา and Lao ຄາ, which in Vientiane Lao is pronounced /kʰáː/, which may sound like Thai ค้า kha /kʰáː/, 'to trade' due to similarity in tone. The same word in some parts of Isan near Roi Et Province would confusingly sound to Thai ears like ขา kha /khǎː/ with a rising tone, where the local tone patterns would have many pronounce the word with a rising-high-falling heavier on the rising. Although a native Thai speaker would be able to pick up the meaning of the similar words of Isan through context, and after a period of time, would get used to the different tones (with most Lao and Isan speech varieties having an additional one or two tones to the five of Thai), it can cause many initial misunderstandings.

Despite the similarities, the Thai and Lao languages have very different speaking styles. Thai speakers tend to use many euphemisms, cute expressions, word play or abbreviations and situations that require 'nuanced' usage or implied meanings. For instance, in relaxed and casual speech, pronouns are normally dropped unless needed for emphasis or disambiguation. With Bangkok serving as Thailand's primary city and home to the majority of media corporations, government, academic, entertainment and infrastructure as well as roughly a quarter of the population in its metropolitan area, the influence of Bangkok's urban slang permeates spoken language of most native Thai speakers.[77]

Lao conversations are often more direct. Although spoken Isan has its own set of flowery language, word play and strategic vocabulary, they are not as commonly invoked in speech but rather feature heavily in the lyrics of local musical forms such as molam and poetry. Lao speakers also tend to use most pronouns, especially the ones for 'I' and 'you' even in relaxed speech. In Thai and Lao, the increased usage of pronouns occurs in formal and polite usage whereas both reduce their usage in relaxed, casual speech. Thus, compared to Thai, Isan conversations can seem more abrupt, serious, formal to the point of distant to Thai speakers. This perception is nevertheless offset by the large number of Isan words that sound like or are cognate to Thai words that are considered vulgar, and the greater use of native Tai vocabulary which may seem simple compared to the generally larger proportion of Indic vocabulary in Thai.[77]

Although the majority of Isan words are cognate with Thai, and Thai influences are even creeping into the vocabulary, many basic words used in everyday conversation are either lacking cognates in Thai, but share them with Lao. Some usages vary only by frequency or register. For instance, the Thai question word 'เท่าไหร่' is cognate with Isan 'เท่าใด' /tʰāo daj/ and Lao 'ເທົ່າໃດ' /tʰāo daj/, but Isan and Lao tend to use a related variant form 'ท่อใด' /tʰɔ̄ː dàj/ and 'ທໍ່ໃດ' /tʰɔ̄ː dàj/, respectively, more frequently, although the usage is interchangeable and preference probably more related to region and person.

In other areas, Isan preserves the older Tai vocabulary. For example, the old Thai word for a 'glass', such as a 'glass of beer' or 'glass of water' was 'จอก' chok /tɕ̀ɔːk/, but this usage is now obsolete as the word has been replaced by Thai 'แก้ว' kaew /kɛ̑ːw/. Conversely, Isan and Lao continue to use 'จอก' and 'ຈອກ' chok to mean 'glass' (of water) as /tɕ̀ɔ̏ːk/, but Isan 'แก้ว' /kɛ̑ːw/ and Lao 'ແກ້ວ' kéo /kɛ̑ːw/ retain the earlier meaning of Thai 'แก้ว' as 'gem', 'crystal' or 'glass' (material) still seen in the names of old temples, such as 'Wat Phra Kaew' or 'Temple of the Holy Gem'. Nonetheless, a lot of cognate vocabulary is pronounced differently in vowel quality and tone and sometimes consonant sounds to be unrecognisable or do not share a cognate at all. For example, Isan บ่ bo /bɔː/ and Lao ບໍ່ /bɔː/ bo are not related to Thai ไม่ /mâj/, mai

• 1 Thai เท่าไหร่ is cognate to Isan เท่าใด, thaodai and Lao ເທົ່າໃດ, thaodai, /tʰāo daj/.
• 2 Thai แก้ว also exists as Isan แก้ว, kaew, and Lao ແກ້ວ,kèo /kɛ̑ːw/, but has the meaning of "gem".
• 3 Thai ทำ also exists as Isan ทำ, tham and Lao ທຳ, tham, /tʰám/.
• 4 Lao ເຮືອນ and Isan เฮือน also exist as formal Thai เรือน, reuan /rɯːan/.
• 5 Thai บ้าน also exists as Isan บ้าน, ban, and Lao ບ້ານ, bane, /bȃːn/.
• 6 Thai จริง also exists as Isan จริง, ching, and Lao ຈິງ, ching, /tɕiŋ/.

These now-obsolete Lao letters were once used to spell words of Pali and Sanskrit derivation, but were removed, reducing the consonant inventory and the similarity of spelling between Thai and Lao.

Isan and Lao have drifted away from each other mostly in terms of the written language. The Isan people were forced to abandon their traditional Tai Noy script and have come to use the Thai written language, or Isan written in Thai, for communication. In Laos, Tai Noy was modified into the modern Lao script, but several spelling changes in the language during the transition from the Lao monarchy to the communist rule moved Thai spelling and Lao spelling of cognate words further apart. Isan, writes all words with Thai cognates as they exist in Thai, with clusters, special letters only found in obscure Sanskrit words and etymological principles that preserve silent letters and numerous exceptions to Thai pronunciation rules although a small handful of Isan words, with no known or very obscure Thai cognates, are spelled more or less the same as they are in Lao.

Lao spelling in Laos was standardised in the opposite direction. Whilst previously written in a mixture of etymological and phonetical spellings, depending on audience or author, the language underwent several reforms that moved the language towards a purely phonetical spelling. During the restoration of the king of Louang Phabang as King of Laos under the last years of French rule in Laos, the government standardised the spelling of the Lao language, with movement towards a phonetical spelling with preservation of a semi-etymological spelling for Pali, Sanskrit and French loan words and the addition of archaic letters for words of Pali and Sanskrit origin concerning Indic culture and Buddhism.

Spelling reforms under the communist rule of Laos in 1975 were more radical, with the complete abolition of semi-etymological spelling in favour of phonetical spelling, with the removal of silent letters, removal of special letters for Indic loan words, all vowels being written out implicitly and even the elimination or replacement of the letter 'ຣ' /r/ (but usually pronounced /l/) in official publications, although older people and many in the Lao diaspora continue to use some of the older spelling conventions. The examples demonstrate the differences between Lao and Isan, using Thai orthography, but also that between archaic and modern Lao, as well as the general pronunciation and spelling practices between Standard Thai and Standard Lao in general.[79]

Numerous loan words from other languages, particularly Sanskrit and Pali, have numerous silent letters, sometimes even syllables, that are not pronounced in either Thai, Isan or Lao. In most cases, one of the final consonants in a word, or elsewhere in more recent loans from European languages, will have a special mark written over it (Thai ' ໌ '/Lao ' ໌ ' known in Isan as karan (การันต์) and Lao as karan/kalan (ກາລັນ/archaic ກາຣັນຕ໌ /kaː lán/).

In reforms of the Lao language, these silent letters were removed from official spelling, moving the spelling of numerous loan words from etymological to phonetical. For instance the homophones pronounced /tɕan/ are all written in modern Lao as ຈັນ CH-^A-N, chan, but these were previously distinguished in writing as ຈັນທ໌ CH-^A-N-[TH] or ຈັນທຣ໌ CH-^A-N-[TH]-[R], 'moon'; ຈັນທ໌ CH-^A-N-[TH] or ຈັນທນ໌ CH-^A-N-[TH]-[N], 'sandalwood' and ຈັນ CH-^A-N, 'cruel.' In Isan, using Thai etymological spelling, the respective spellings are จันทร์ CH-^A-N-[TH]-[R], จันทน์ CH-^A-N-[TH]-[N] and จัน, CH-^A-N, with the latter being a shared Lao-Isan word with no Thai cognate.

'Vientiane'

• Thai เวียงจันทน์ /wiaŋ tɕan/, wiangchan and Isan เวียงจันทน์ /ʋíaŋ tɕàn/, E-W-^I-Y-NG-CH-^A-N-TH-[N]
• Archaic Lao ວຽງຈັນທນ໌/ວຽງຈັນທ໌ V-Y-NG-CH-^A-N-[TH]/V-Y-NG-CH-^A-[TH] and modern Lao ວຽງຈັນ V-Y-NG-CH-A-N, /ʋíaŋ tɕàn/
• Derives from Lao ວຽງ, viang or 'walled city' and Sanskrit chandna (चन्दन tʃand̪ na/), 'sandalwood'.

'gear'

• Thai เกียร์ /kia/, kia and Isan เกียร์ /kiːa/, E-K-^I-Y-[R]
• Archaic Lao ເກັຽຣ໌ E-K-^I-Y-[R] and modern Lao ເກັຽ E-K-^I-Y, /kiːa/
• Derives from English 'gear' /ɡɪə/ (UK) or /ɡɪər/ (US).

'animal'

• Thai สัตว์ /sàt/, sat and Isan สัตว์ /sát/, S-^A-T-[W]
• Archaic Lao ສັຕວ໌ S-^A-T-[W] and modern Lao ສັດ S-^A-D, /sát/
• Derives from Sanskrit सत्त्वं, sattvam (/sat̪ tʋam/), 'living being'.

The oldest texts in the Tai Noy corpus show that the earliest stages of the Lao language had consonant clusters in some native words as well as many loan words from Khmer, Mon, other Ausroasiatic languages, Sanskrit and Pali. Although most of these were maintained in Thai pronunciation, these clusters were quickly abandoned, indicating that the Tai dialects that became the Lao language lacked them or that they lost them through separate language development. Unlike the Thai script, Lao preserves a subscript version of /l/ and /r/ ' ຼ ' that was commonly used in the ancient Tai noy script when these clusters were pronounced and written.

Some consonant clusters were maintained in the Lao language for some vocabulary, mostly of Sanskrit and Pali derivation and used in royalty or religious settings, but the most recent spelling reforms in the Lao language removed most of them. The Thai language has preserved all of them, and when Isan is written in Thai, cognates of Thai words are spelled as if they are pronounced in Thai, with consonant clusters that are usually not pronounced in Isan except some religious and technical terms.

'garlic'

• Thai กระเทียม krathiam /kràʔ tʰíam/ and Isan กระเทียม /káʔ tʰíam/, K-R-A-E-TH-^I-Y-M
• Ancient Lao ກຼະທຽມ/ກຣະທຽມ K-_L/R-A-T-Y-M/K-R-A-T-Y-M and modern Lao ກະທຽມ K-A-T-Y-M, kathiam /káʔ tʰíam/

'country'

• Thai ประเทศ phrathet /pràʔ tɛ̂t/ and Isan ประเทศ /páʔ tʰɛ̂t/, P-R-A-E-TH-S
• Ancient Lao ປຼະເທສ/ປະເທສ P-_L/R-A-E-TH-S/P-R-A-E-TH-S and modern Lao ປະເທດ P-A-E-T-D, phathèt /páʔ tʰɛ̂t/
• Derives from Sanskrit pradeśa (प्रादेश /prād̪eɕā/), 'country' or 'nation'

'to be entertained'

• Thai เพลินจิต ploenchit /pʰlɤn tɕìt/ and Isan เพลินจิต /pʰɤ́n tɕít/, E-PH-L-^I-N-CH-^I-T
• Ancient Lao ເພີຼນຈິຕ/ເພລີນຈິຕ E-PH-_L/R-^I-N-CH-^I-T/E-PH-L-^I-N-CH-^I-T and modern Lao ເພີນຈິດ E-PH-^I-N-CH-^I-D, phuenchit /pʰɤ́n tɕít/

'to be finished'

• Thai เสร็จ set /sèt/ and Isan เสร็จ /sét/, E-S-R-CH
• Ancient Lao ເສັຼດ E-S-_L/R-D modern Lao ເສັດ E-S-D, /sét/
• Derives from Khmer srac (ស្រេច /sratɕ/)

'Buddha'

• Thai พระพุทธเจ้า, Phra Phuttha Chao /pʰráʔ pʰút táʔ tɕâu/ and Isan พระพุทธเจ้า /pʰūt tʰāʔ tɕâu/, PH-R-A-PH-_U--TH-TH-E-CH-A
• Archaic Lao ພຣະພຸດທະເຈົ້າ/(rare) ພຼະພຸດທະເຈົ້າ PH-R-A-PH-U-D-TH-A-E-CH-A/PH-_L/R-A-PH-_U-D-TH-A-E-CH-A and modern Lao ພຣະພຸດທະເຈົ້າ/ພະພຸດທະເຈົ້າ PH-R-A-PH-_U-D-TH-A-E-CH-A/PH-A-PH-_U-D-TH-A-E-CH-A, Phra Phouttha Chao /pʰūt tʰāʔ tɕâu/
• Derives from Lao ພຣະ, phra or 'holy/royal', Sanskrit/Pali Buddha (बुद्ध /bud̪d̪ʱa/) and Lao ເຈົ້າ, chao or 'prince/lord.'

As consonants may have one value at the start of a consonant and one at the end, occasionally the same letter will be used to end one syllable and begin the next. This remains common in many loan words from Sanskrit and Pali, and was once the case in Lao orthography, but now the different consonant sounds are written out explicitly and no longer implied from older and confusing rules of spelling. Thai, with its etymological spelling, preserves the implied pronunciation of these geminated consonant groupings.

'girl of noble birth'

• Thai กุลนารี kunlanari /kun láʔ naː riː/ and Isan กุลนารี /kun lāʔ náː lí/, K-_U-L-N-A-R-^I
• Archaic Lao ກຸລນາຣີ/ກຸນລະນາຣີ K-_U-L-N-A-R-^I/K-_U-N-L-A-N-A-R-^I and modern Lao ກຸນລະນາລີ K-_U-N-L-A-N-A-L-^I, kounlanari /kun lā náː líː/
• Derives from Sanskrit kulanārī (कुलनारी /kulanaːriː/)