Traditional English pronunciation of Latin

Latin stress is predictable. It falls on the penultimate syllable when that is "heavy", and on the antepenultimate syllable when the penult is "light".

In Greek, stress is not predictable, but it may be ignored when pronouncing Greek borrowings, as they have been filtered through Latin and have acquired the stress patterns of Latin words.

A syllable is "light" if it ends in a single short vowel. For example, a, ca, sca, scra are all light syllables for the purposes of Latin stress assignment.

Any other syllable is "heavy":

• if it is closed (ended) by a consonant: an, can, scan, scran
• if the vowel is long or a diphthong in Latin, or in the Latin transliteration of Greek: ā, cā, scā, scrā (a long vowel) or æ, cæ, scæ, scræ (a diphthong).

Latin diphthongs may be written ⟨æ⟩ or ⟨ae⟩, ⟨œ⟩ or ⟨oe⟩. Long vowels are written with a macron: ā ē ī ō ū ȳ, though this is a modern convention. Greek long vowels are ει, η, ου, ω, sometimes ι, υ, and occasionally α. (Long α is uncommon.) For example, Actaeon is pronounced /ækˈtiːɒn/ ak-TEE-on or /ækˈtiːən/ ak-TEE-ən. A diaeresis indicates that the vowels do not form a diphthong: Arsinoë /ɑːrˈsɪnoʊiː/ ar-SIN-oh-ee (not *AR-sin-ee).

The importance of marking long vowels for Greek words can be illustrated with Ixion, from Greek Ἰξίων. As it is written, the English pronunciation might be expected to be */ˈɪksiɒn/ IK-see-on. However, length marking, Ixīōn, makes it clear that it should be pronounced /ɪkˈsaɪɒn/ ik-SY-on.

When a consonant ends a word, or when more than a single consonant follows a vowel within a word, the syllable is closed and therefore heavy. (A consonant is not the same thing as a letter. The letters x [ks] and z [dz] each count as two consonants, but th [θ], ch [k], and ph [f] count as one, as the pronunciations in brackets indicate.) The English letter j was originally an i, forming a diphthong with the preceding vowel, so it forces the stress just as æ, œ, z, and x do.

• Exception: a consonant cluster of p, t, or c/k plus l or r is ambiguous. The preceding syllable may be considered either open or closed. For example, the name Chariclo (Chariklō) may be syllabified as either cha-rik-lō, with a closed penult, or cha-ri-klō, with an open penult, so both /kəˈrɪkloʊ/ kə-RIK-loh and /ˈkærɪkloʊ/ KARR-ik-loh are accepted pronunciations in English.

If more than two syllables precede the stressed syllable, the same rules determine which is stressed. For example, in Cassiopeia (also Cassiopēa), syllabified cas-si-o-pei-a, the penult pei/pē contains a long vowel/diphthong and is therefore stressed. The second syllable preceding the stress, si, is light, so the stress must fall one syllable further back, on cas (which coincidentally happens to be a closed syllable and therefore heavy). Therefore, the standard English pronunciation is pronounced /ˌkæsiəˈpiːə, -sioʊ-/ KAS-ee-ə-PEE-ə, -⁠see-oh-[5] (note however that this word has the additional irregular pronunciation of /ˌkæsiˈoʊpiə/ KAS-ee-OH-pee-ə).

Whether a vowel letter is pronounced "long" in English (/eɪ, iː, aɪ, oʊ, juː/) or "short" (/æ, ɛ, ɪ, ɒ, ʌ/) is unrelated to the length of the original Latin or Greek vowel. Instead it depends on position and stress. A vowel followed by a consonant at the end of a word is short in English, except that final -es is always long, as in Pales /ˈpeɪliːz/ PAY-leez. In the middle of a word, a vowel followed by more than one consonant is short, as in Hermippe /hərˈmɪpi/ hər-MIP-ee, while a vowel with no following consonant is long. However, when a vowel is followed by a single consonant (or by a cluster of p, t, c/k plus l, r) and then another vowel, it gets more complicated.

• If the syllable is unstressed, it is open, and the vowel is often reduced to schwa.
• If the penultimate syllable is stressed, it is open and the vowel long, as in Europa /jʊəˈroʊpə/ yoor-OH-pə.
• If any other syllable is stressed, it is closed and the vowel is short, as in Ganymede /ˈɡænɪmiːd/ GAN-im-eed and Anaxagoras /ˌænəkˈsæɡərəs/ AN-ək-SAG-ər-əs.

Regardless of position, stressed u stays long before a single consonant (or a cluster of p, t, c/k plus l, r), as in Jupiter /ˈdʒuːpɪtər/ JOO-pit-ər.

• Exception: A stressed nonhigh vowel (a, e, o) stays long before a single consonant (or cluster of p, t, c/k plus l, r) followed by an /i/ or /iː/ ee sound (e, i, y) plus another vowel at the end of a word: Proteus /ˈproʊtiːəs/ PROH-tee-əs, Demetrius /dɪˈmiːtriəs/ dim-EE-tree-əs. This is because, historically and regionally, in many of these words the e, i, y is pronounced /j/ y and combines with the following syllable, so that the preceding syllable is penultimate and therefore open: /ˈproʊ.tjuːs/ PROH-tyooss.

Traditionally, English syllables have been described as 'open' when their vowel (in English) is long and they are followed by a single consonant followed by another vowel, and as 'closed' in the same environment when their vowel is short. However, it is debated how accurate this analysis is, as in English syllables tend to attract a following consonant, especially when they are stressed, so that all stressed syllables followed by a consonant are arguably 'closed'. Such following consonants are sometimes described as ambisyllabic. This effect is especially apparent in some dialects, such as RP, when the consonant in question is /r/, which affects the quality of the preceding vowel. None of this changes the patterns described in this article: The long-short distinction described above is maintained regardless. For example, the 'e' in Hera is long regardless of whether it is pronounced /ˈhiːrə/ or /ˈhɪərə/ in a particular dialect, or analyzed as open HEE-rə or as closed HEER-ə. American dictionaries tend to follow the former transcription, and British dictionaries the latter, so when the consonant 'r' is involved the rules for the English pronunciation of Latin words are more straightforward when using the conventions of American dictionaries.

Anglo-Latin includes a large amount of Greek vocabulary; in principle, any Greek noun or adjective can be converted into an Anglo-Latin word. There is a conventional set of equivalents between the letters of the Greek and Roman alphabets, which differs in some respects from the current mode of Romanizing Greek. This is laid out in the tables below:

Rh is used for Greek ρ at the beginnings of words, e.g. ῥόμβος (rhombos) > rhombus. Rarely (and mostly in words relatively recently adapted from Greek), k is used to represent Greek κ. In such cases it is always pronounced [k] and never [s] (as it might be if spelled c) : e.g. σκελετός (skeletos) > skeleton not "sceleton".

Greek accent marks and breath marks, other than the "rough breathing" (first in the list of consonants above), are entirely disregarded; the Greek pitch accent is superseded by a Latin stress accent, which is described below.

Frequently, but not universally, certain Greek nominative endings are changed to Latin ones that cannot be predicted from the tables above. Occasionally forms with both endings are found in Anglo-Latin, for instance Latinized hyperbola next to Greek hyperbole. The most usual equations are found below:

Examples:

• Greek ἄγγελος (aggelos) > Latin angelus (γγ > ng, -ος > us)
• Greek ἔλλειψις (elleipsis) > Latin ellipsis (ει > i (shortened before ps), ψ > ps)
• Greek μουσεῖον (mouseion) > Latin mūsēum (ου > ū, ει > ē, -ον > um)
• Greek μαίανδρος (maiandros) > Latin mæander (αι > æ, -ρος > er)
• Greek χρυσάνθεμον (chrȳsanthemon) > Latin chrȳsanthemum (χ > ch, υ > y, θ > th, -ον > um)
• Greek διάῤῥοια (diarroia) > Latin diarrhœa (ῤῥ > rrh, οι > œ)

• The letters b, f, k, l, m, p, v and z have each only one sound, which corresponds to the equivalent IPA symbols /b f k l m p v z/.
• The letter j has the single sound /dʒ/.
• The letter r has a single sound, /r/ in rhotic dialects of English. In nonrhotic dialects, it varies according to placement in a syllable. At the beginning of a syllable, it is pronounced /r/. At the end of a syllable, i.e. between a vowel and a consonant, or after a vowel at the end of a word, it is dropped—though not without, frequently, affecting the pronunciation of the previous vowel sound. If r occurs at the end of a word after a vowel, and the next word begins with a vowel, it is usually pronounced as the beginning of the first syllable of the next word. Rh and rrh are pronounced exactly like r and rr.
• When followed by a vowel, the combinations qu (always) and gu and su (usually) stand for /kw/, /ɡw/, and /sw/ respectively.
• The combination ph is pronounced /f/.
• The combination th is pronounced /θ/.
• The combination ch is pronounced /k/ in all environments - although in Scottish pronunciation it is pronounced /x/ at the end of a syllable.
• The letters c, d, g, h, n, s, t, x have different values depending upon surrounding sounds and syllable structure.

The underlying consonantal phonemes of Anglo-Latin are close in most respects to those of Latin, the primary difference being that /w/ and /j/ are replaced in Anglo-Latin by /v/ v and /dʒ/ j. The sound /θ/ th was borrowed from Greek.

Several word-initial clusters, almost all derived from Greek, are simplified in Anglo-Latin by omitting the first consonant:

• βδ bd becomes /d/: bdellium
• τμ tm becomes /m/: tmesis
• κν cn, γν gn, μν mn and πν pn become /n/: Cnossus, gnosis, Mnemosyne, pneumonia
• ψ ps becomes /s/: psyche
• κτ ct and πτ pt become /t/: Ctesiphon, ptosis
• χθ chth and φθ phth become /θ/: Chthon, phthisis
• ξ x becomes /z/: Xanthippe

In the middle of words both consonants in these clusters are pronounced (e.g. Charybdis, Patmos, Procne, prognosis, amnesia, apnœa, synopsis, cactus, captor); medial chth and phth are pronounced /kθ/ and /fθ/ respectively, as in autochthon and naphtha.

The letters c, d, g, h, n, s, t and x have different sounds (phonemes) depending upon their environment: these are listed summarily below.

The full set of consonantal phonemes for Anglo-Latin is almost identical to that of English, lacking only /ð/.

Environments that condition the appearance of some of these phonemes are listed below:

The change of intervocalic /s/ to /z/ is common but not universal. Voicing is more common in Latin than in Greek words, and never occurs in the common Greek ending -sis, where s is always voiceless: basis, crisis, genesis.

The most common type of phonemic change in Anglo-Latin is palatalization. Anglo-Latin reflects the results of no less than four palatalization processes. The first of these occurred in Late Latin, the second in Proto-Gallo-Romance, the third and fourth within the history of English. While the first two palatalizations are universally used in variants of Anglo-Latin, the third and especially the fourth are incompletely observed in different varieties of Anglo-Latin, leading to some variant pronunciations.

• Palatalization 1 affected only the sound of t, converting it to /ts/ when it preceded a semivowel i (at that stage pronounced /j/) and did not follow s, t, or x. This /ts/ sound eventually merged with /s/ and was subject to further changes in Palatalization 3. When /t/ followed /s/ or /t/ it did not change; in some cases it might later change to /tʃ/ by Palatalization 4. Note that t did not change to /s/ before semivowel e, but remained /t/ as in confiteor.
• Palatalization 2 affected the sounds of c and g, converting them to /ts/ and /dʒ/; the /ts/ arising from c merged with the /ts/ arising from t, and both shared further developments of this sound, turning to /s/. When geminate (double), palatalized cc and gg were affected diversely; only the second c in cc was palatalized, producing the sound /ks/, as in successor; but both gs in gg were palatalized, producing a /dʒ/ sound, as in "exaggerate".
• Palatalization 3 affected /s/ and /z/ of whatever origin, changing them to /ʃ/ and /ʒ/.
• Palatalization 4 affected /s/ and /z/ exactly as Palatalization 3 did, but also affected /t/ and /d/, changing them to /tʃ/ and /dʒ/

Some of the occasions on which palatalizations 3 and 4 fail to take effect should be noted:

• Palatalization 3 fails: asphyxia, Cassiopeia, dyspepsia, excelsior, exeunt, gymnasium, symposium, trapezium. Note that the semivowel i is always pronounced as a full vowel /i/ in these cases. In some dialects Palatalization 3 frequently fails when another /ʃ/ sound follows, as in "enunciation", "pronunciation", "appreciation", "glaciation", "association", with the /s/ sound then generalized to closely related forms ("enunciate", "appreciate", "associate").
• Palatalization 4 fails (in some dialects): cæsura, fistula, pæninsula, pendulum.

Summary

See further the section on the "semivowel" below.

Following all of the above sound changes except palatalizations 3 and 4, "geminate" sequences of two identical sounds (often but not always double letters) were degeminated, or simplified to a single sound. That is, bb, dd, ff, ll, mm, nn, pp, rr, ss, tt became pronounced /b d f l m n p r s t/. However, for the purposes of determining whether a syllable is open or closed, these single consonants continue to act as consonant clusters.

Other notable instances involving degemination include:

• cc developed two pronunciations:
  • before a front vowel (e, æ, œ, i, y) cc is pronounced /ks/, and as it consists of two distinct sounds, is not degeminated.
  • before a back vowel (a, o, u) cc was pronounced /kk/ which degeminated to simply /k/
• cqu /kkw/ degeminated to /kw/
• gg also has two pronunciations:
  • before a front vowel, gg is pronounced /dʒ/ after degemination.
  • before a back vowel, gg is pronounced /ɡ/ after degemination.
• sc before a front vowel was pronounced /ss/, and degeminated to /s/.
• sc and ss before the "semivowel" are pronounced /ʃ/

The following combinations, derived from Greek, are also pronounced as single consonants:

• κχ cch is pronounced /k/: Bacchus
• πφ pph is pronounced /f/: Sappho
• τθ tth is pronounced /θ/: Pittheus

Openness is a quality of syllables, by which they may be either open, semiopen, semiclosed, or fully closed.

Fully closed syllables are those in which the vowel in the middle of the syllable (the vocalic nucleus) is followed by at least one consonant, which ends or "closes" the syllable. Vowels in fully closed syllables appear:

• At the end of a word followed by at least one consonant, e.g. plus, crux, lynx.
• In the middle of a word followed by two or more consonants. The first of these consonants "closes" the syllable, and the second begins the following syllable; thus a word like lector consists of the two closed syllables lec and tor. Sequences of three or more consonants may be broken up in different ways (e.g., sanc.tum, sculp.tor, ul.tra, ful.crum, ex.tra) but nothing depends upon the exact way in which this is done; any sequence of three or more consonants creates a closed syllable before it. The letter x is equivalent to cs, and as such also closes a syllable; a word like nexus is syllabified nec.sus, and consists of two closed syllables.
• Two successive consonants of identical pronunciation are always pronounced as a single consonant in Anglo-Latin. When such a consonant sequence follows a penult syllable, the syllable counts as closed for the purposes of determining the position of stress: ba.cíl.lus, di.lém.ma, an.tén.na, co.lós.sus; they also prevent a penult syllable from lengthening, as in the previous examples and also pal.lor, com.ma, man.na, cir.rus, cas.si.a, pas.sim, glot.tis. They also count as closed for the purpose of determining whether a u is open or closed. In these respects they act precisely like syllable-closing consonant sequences, although they are pronounced as single sounds. (In words like successor the two c's do not merge, because each of them has a different sound—/k/ and /s/, respectively.)
• Certain sequences of consonants do not close syllables: these include all instances of obstruents (stops and fricatives) followed by r, including br, cr, chr, dr, gr, pr, tr, thr. Thus words like supra and matrix are syllabified as su.pra and ma.trix, and the first syllable of both words is open; likewise a.cro.po.lis, di.plo.ma, de.tri.tus. The sequence /kw/ (spelled qu) also does not close the preceding syllable; i.e., one syllabifies re.qui.em and not req.ui.em.
• Sequences of obstruents followed by l are less consistent. The sequences cl, chl, gl and pl do not close a syllable, e.g. nu.cle.us, du.plex with open first syllables; but the sequences bl, tl, thl do close a syllable, producing the syllabifications Pub.li.us, at.las, pen.tath.lon, with closed syllables before the l.

Semiclosed syllables are closed, unstressed syllables that had been closed and became open due to the merger of two following consonants of the same sound. For the purpose of determining vowel reduction in initial unstressed syllables they count as open.

• Double consonants following an initial syllable containing a, e, i, o merge to count as one consonant: a.(c)cumulator, a.(g)gres.sor, ca.(l)li.o.pe, a.(p)pen.dix, e.(l)lip.sis, co.(l)lec.tor, o.(p)pres.sor, o.(p)pro.bri.um. The first syllables of all these words are only partially closed, and the vowels are reduced.
• The same phenomenon occurs after u, but note that the u is both closed and reduced: su.(p)pres.sor, su.(c)ces.sor, cu.(r)ri.cu.lum.

Semiopen syllables are syllables that had been closed and unstressed, and that are followed by a sequence of consonants that can stand at the beginning of a syllable. Since instances of obstruents +r or l are already considered open, semiopen syllables are practically restricted to instances of s + obstruent, bl, and in some cases perhaps tl. Vowels in initial semiopen syllables may be treated as open for all purposes except for determining the value of u, which is still closed in semiopen syllables.

• When s is followed by a consonant, s syllabifies with the following consonant: a.spa.ra.gus, pro.spec.tus, na.stur.ti.um, a.sphyc.si.a (asphyxia). S also syllabifies with a following palatalized c (pronounced [s]): a.sce.sis, pro.sce.ni.um. When s syllabifies with a following consonant, the preceding syllable counts as semi-open. Possible exceptions are pos.te.ri.or, tes.ta.tor.
• Other sequences of consonants fully close an initial unstressed syllable and produce a short vowel: an.ten.na, am.ne.si.a, bac.te.ri.um, mag.ni.fi.cat, mac.sil.la (maxilla), spec.ta.tor, per.so.na, oph.thal.mi.a, tor.pe.do.

See further the section on initial unstressed syllables below.

Open syllables are those in which the nucleus is followed:

• By no consonant at the end of the word: pro, qua.
• By a vowel in the middle of a word : oph.thal.mi.a, fi.at, cor.ne.a, cha.os, chi.as.mus, a.ma.nu.en.sis.
• By only a single consonant in the middle of a word: sta.men, æ.ther, hy.phen, phœ.nix, ter.mi.nus, a.pos.tro.phe.
• By those consonant clusters that do not fully or partially close a syllable In the middle of a word : ma.cron, du.plex, Cy.clops, tes.ta.trix, a.cro.po.lis.

Stress is another characteristic of syllables. In Anglo-Latin, it is marked by greater tension, higher pitch, lengthening of vowel, and (in certain cases) changes in vowel quality. Its exact concomitants in Classical Latin are uncertain. In Classical Latin the main, or primary stress is predictable, with a few exceptions, based on the following criteria:

• In words of one syllable, stress falls on that syllable, as marked in the following syllables with an acute accent: quá, nón, pár.
• In words of two syllables, stress falls on the first syllable of the word (the penult, or second from the end): e.g., bó.nus, cír.cus.
• In words of three or more syllables, stress falls either on the penult or the antepenult (third from the end), according to these criteria:
  • If the penult contains a short vowel in an open syllable, the stress falls on the antepenult: e.g., stá.mi.na, hy.pó.the.sis.
  • If the penult contains a long vowel; a diphthong; a closed syllable (with any length of vowel); or is followed by z, the stress falls on the penult.
    • Long vowel: cicāda > cicáda, exegēsis > exegésis.
    • Diphthong: amóeba, Acháia, paranóia, thesáurus
    • Closed syllable: aórta, interrégnum, prospéctus, rotúnda
    • z: horízon

Primary stress can therefore be determined in cases where the penult is either closed or contains a diphthong. When it contains a vowel that may have been either short or long in Classical Latin, stress is ambiguous. Since Anglo-Latin does not distinguish short from long vowels, stress becomes a lexical property of certain words and affixes. The fact that decorum is stressed on the penult, and exodus on the antepenult, is a fact about each of these words that must be memorized separately (unless one is already familiar with the Classical quantities, and in the former case, additionally with the fact that decus -ŏris n. with short -o- syllable became in late Latin decus/decor -ōris m. with long -o- syllable: Dómine, diléxi decórem domus tuæ).

Secondary stress is dependent upon the placement of the primary stress. It appears only in words of four or more syllables. There may be more than one secondary stress in a word; however, stressed syllables may not be adjacent to each other, so there is always at least one unstressed syllable between the secondary and primary stress. Syllables containing semivowel e or i are never stressed.

• If a four-syllable word has primary stress on the antepenult, there is no secondary stress: pa.rá.bo.la, me.tá.the.sis.
• If a four-syllable word has primary stress on the penult, secondary stress is on the first syllable, marked hereafter with a grave accent: à.la.bás.ter, è.pi.dér.mis, sì.mu.lá.crum, prò.pa.gán.da, ùl.ti.má.tum.
• If a 5-syllable word has primary stress on the antepenult, secondary stress is on the first syllable: hìp.po.pó.ta.mus, Sà.git.tá.ri.us, Phì.la.dél.phi.a.

Secondary stress in words with three or more syllables before the primary stress is less predictable. Such words include those of five syllables with penult primary stress, and all words of six syllables in length or longer. The following generalizations about such long words may be made:

• The syllable immediately before the primary stress is never stressed.
• Words produced by derivation from a shorter word convert the primary (and, if any, secondary) stress of the stem into a secondary stress, as long as it does not fall immediately before the new primary stress: é.le.phant- + í.a.sis becomes è.le.phan.tí.a.sis
• Compounds of which the compound element consists of more than one syllable likewise convert the primary stress of their elements into secondary stress: phár.ma.co- + póei.a becomes phàr.ma.co.póei.a.
• If a primary stress is eliminated in compounding or derivation because it would stand next to another stress, secondary stress remains unchanged: pùsillánimus + itas becomes pùsillanímitas.
• Single-syllable prefixes and single-syllable compound elements are generally unstressed: ac.cù.mu.lá.tor, im.pè.di.mén.ta, Her.mà.phro.dí.tus
• In other cases where the composition of the word may be unclear, every other syllable before the primary stress may be stressed: a.mà.nu.én.sis, ò.no.mà.to.póei.a. In some cases the third syllable before the primary stress is stressed when the second syllable is light, just as when assigning the primary stress.

Unstressed syllables are all others. They are always adjacent to a stressed syllable; that is, there can never be more than two unstressed syllables in a row, and that only when the first one follows a stressed syllable.

The most notable distinction between Anglo-Latin and other varieties of Latin is in the treatment of the vowels. In Anglo-Latin, all original distinctions between long and short vowels have been obliterated; there is no distinction between the treatment of a and ā, etc., for instance. However, the subsequent development of the vowels depended to a large degree upon Latin word stress (which was preserved nearly unchanged in the medieval period), and as this was in part dependent upon vowel length, in certain cases Latin vowel length contrasts have been preserved as contrasts in both stress and quality. However, the immediate governing factor is not length but stress: short vowels that were stressed for various reasons are treated exactly like stressed long vowels.

In addition to the merger of long and short vowels, other vowel mergers took place:

• the diphthongs æ and œ merged with e
• the vowels i and y merged
• the diphthong ei (also æi, œi), when still written distinctively, in pronunciation was merged with i or (more frequently) e

The merger of æ and œ with e was commonly recognized in writing. Sometimes forms written with æ and œ coexist with forms with e; in other cases the form with e has superseded the diphthong in Anglo-Latin. Consider the following:

• æon and eon, æther and ether, amœba and ameba, anæmia and anemia, anæsthesia and anesthesia, cæsura and cesura, chamæleon and chameleon, dæmon and demon, diæresis and dieresis, encyclopædia and encyclopedia, fæces and feces, fœtus and fetus, hyæna and hyena, prætor and pretor

The following words are usually spelled with e, though they originally had æ:

• ænigma > enigma, æquilibrium > equilibrium, æra > era, Æthiopia > Ethiopia, diarrhœa > diarrhea, mæander > meander, musæum > museum, œsophagus > esophagus, pæninsula > peninsula, præcentor > precentor, prædecessor > predecessor, præmium > premium, præsidium > presidium, tædium > tedium

In other cases, particularly names, the forms with the diphthongs are the only correct spelling, e.g., ægis, Cæsar, Crœsus, Œdipus, onomatopœia, pharmacopœia, Phœbe, phœnix, Piræus, sub pœna.

The sequences ei, æi, œi (distinguished in writing and pronunciation from ej, the vowel followed by a consonant, as in Sejanus) are sometimes retained in spelling preceding a vowel. In such cases the sequence is invariably pronounced as a simple vowel, sometimes i (as in meiosis, pronounced as if miosis), sometimes e (as in Cassiopeia, Deianira, onomatopœia, pronounced as if Cassiopea, Deanira, onomatopea), and sometimes either (Pleiades, commonly pronounced as if Pleades or Pliades).

The result was a system of five vowels, a, e, i, o, u. These would subsequently split, according to their environment, into long, short, and (eventually) unstressed variants; and these variants would eventually also be altered based on neighboring sounds. However, in phonemic terms, Anglo-Latin still has only five vowels, with multiple allophones.

In addition, there were the diphthongs, ai, oi, ui, au and eu. Of these, ai and au eventually monophthongized, eu merged with the open variant of u, and yi merged with the "long" i. Only oi and ui remained as true diphthongs, but both are extremely rare.

The vowels a, e, i, o each have three primary variants: long, short, and reduced. Each of these may, in turn, exhibit allophonic variation based on features of its phonetic environment, including whether it is stressed, whether it is in an open or closed syllable, where it is positioned in the word, and what consonants are next to it. One of the most common environmental causes of vowel alteration is the presence of a following r. Vowels altered by a following "r" are called "r-colored".

This is the default value for vowels, observed:

1. In closed monosyllables
2. In stressed closed penult syllables
3. In all antepenult syllables, open or closed, which receive primary stress, except for those lengthened due to a following semivowel
4. In all syllables with secondary stress
5. In fully closed unstressed syllables which immediately precede, but do not follow, a primary or secondary stress (usually in the first syllable of a word), with exceptions for certain prefixes

All short vowels have variants colored by a following r sound when the r is followed by a different consonant (not r) or by the end of the word. In addition, there is a variant of short a that only appears after a /w/ sound – chiefly found in the sound qu /kw/. This is a relatively recent phonetic development in English and Anglo-Latin, so it wasn't present in earlier stages of Anglo-Latin.

Exceptionally, monosyllables ending in es are pronounced with the rhyme /iːz/, e.g., pes, res. This pronunciation is borrowed from that of -es used as an ending.

Exceptions to the pronunciation of short y generally involve prefixed elements beginning with hy- in an open syllable, such as hydro- and hypo-; these are always pronounced with a long y, e.g. hydrophobia, hypochondria. This pronunciation is the result of hypercorrection; they used to be pronounced with a short /ɪ/, as is still the case in the word "hypocrite" and (for some speakers and formerly commonly) hypochondria.

Prefixes may also behave in anomalous ways:

1. The prefix ob- in unstressed syllables may be reduced to /əb/, even when it closes a syllable: cf. "obsession, oblivion".
2. The Greek prefix en-, em- in a closed unstressed syllable may be reduced to /ɪn, ən/, /ɪm, əm/: encomium, emporium.
3. The prefix ex- in an unstressed syllable may be reduced to /əks/, /əɡz/, despite always being in a closed syllable: exterior, exemplar.
4. The prefix con-, com- is reduced to /kən/, /kəm/ when unstressed: consensus, compendium, regardless of whether the syllable is closed or not.
5. The preposition and prefix post(-) is anomalously pronounced with "long o": /poʊst/: post-mortem and cf. "postpone"; also thus in words in which post was originally a preposition (postea, postquam) but not in other derivatives, being pronounced with short o in posterus, posterior, postremo, postridie.

Long vowels are those that historically were lengthened. By virtue of subsequent sound changes, most of these are now diphthongs, and none is distinguished by vowel length—however, the term "long" for these vowels is traditional. "Long" vowels appear in three types of environments:

1. a, e, i and o are long in an open monosyllable
2. a, e, i and o are long in a stressed open penult syllable
3. a, e and o are long when in an open syllable followed by semivocalic i and e
4. a and o are long when they precede another vowel in hiatus; i and e are long in the same environments, but only when they are not semivocalic (i. e., when they are in the initial syllable or receive primary stress). Hiatus may be original, or may arise from the deletion of h between a stressed and unstressed syllable

Reduced vowels appear in unstressed syllables, except for:

• Closed initial unstressed syllables, which are generally short.
• Certain unstressed final syllables.

A variety of possible realizations are available for open, semiopen, and semiclosed initial unstressed syllables, including (for e and i) long, short, and reduced variants. Fully closed initial unstressed syllables are always short.

* A "schwi". It generally conflates with /ɪ/ in RP and with schwa in Australia. Directly before another vowel it may be the 'HAPPY' vowel.

** A rounded schwa. It has a w-like offglide before another vowel the way /oʊ/ does, but otherwise in many dialects it conflates with schwa.

The variation in the value of the initial open unstressed vowel is old. Two different types of variation can be distinguished; the older use of a "long" vowel for i, y, o (and their variants); and more recent variations in the value of the reduced vowel.

No completely general rule can be laid down for the appearance of an initial unstressed long vowel, although such vowels must have appeared before the shortening of geminate consonants, as they are restricted to fully open syllables. The most general tendency is for long vowels to appear when i and y are either preceded by no consonant or by h, e.g., idea, isosceles, hyperbola, hypothesis. The prefixes in and syn never have long vowels: inertia, synopsis. I and y also tend to be short when the next syllable contains an i or y, short or long: militia, divisor.

O is a little less likely to appear with a long value in this location; or, at any rate, it is harder to distinguish the long value from the reduced vowel.

Unstressed e and i in open syllables had merged by the early 17th century; their reduced reflex is often transcribed [ə], but by many speakers is still pronounced as a high front lax vowel, distinct from the [ə] derived from a, here transcribed ⟨ᵻ⟩. For such speakers, the first syllables in Demeter and Damascus are pronounced differently.

Unstressed o, also often transcribed [ə], is by many speakers pronounced with considerable lip-rounding, here transcribed ⟨ᵿ⟩.

The partially closed initial unstressed vowels began as short vowels, but were later reduced.

These are the same sounds as in the preceding chart, but without the option of the "long" vowels and much less rounding of the o.

proscenium does not fall in this group, apparently because felt to be pro+scenium.

All vowels in medial unstressed syllables are reduced to /ə/ or /ɪ/, regardless of whether they are in open or closed syllables.

The pronunciation of the letter u does not depend upon stress, but rather upon whether the syllable in which it appears is open or closed. There are no "long" and "short" variants of either type of u, but there are reduced and r-colored variants of both types.

The underlying sound of open u is /juː/; it shares developments with the homophonous diphthong eu, which can however appear in closed syllables.

The sound [j] in /juː/ and its variants is deleted in various environments:

• After palatal consonants (/ʃ tʃ ʒ dʒ/), whether original or resulting from the merger of /j/ and the preceding consonant, in both stressed and unstressed syllables; e.g. /dʒ/: junior, Julius, Jupiter, cæsura, educator, spatula, fistula

After the following consonants when they precede u in an initial, final, or stressed syllable:

• /r/ and /l/: rumor, verruca, luna, Lucretia, Pluto, effluvium
• /s/, /z/ (except in conservative speech): super, superior, Vesuvius, and variably Zeus

In some dialects, particularly of American English, /j/ is deleted after all dental/alveolar consonants when they precede u in an initial, final or stressed syllable:

• /d/, /n/, /t/ and /θ/: duplex, caduceus, medusa, nucleus, lanugo, tutor, Thucydides
• For some speakers, /juː/ is pronounced [ɪu] following these consonants.

/j/ is not deleted in the following environments:

• When u is the first letter of the word or follows /h/: uterus, humerus
• Following a vowel: Ophiuchus
• Following labials /p b f v m/: pupa, furor, nebula, uvula, musæum
• Following velars /k ɡ/ : cumulus, lacuna, Liguria
• When it is in an interior unstressed syllable not following a palatal consonant, /j/ remains after a single consonant even when it might be deleted in a stressed syllable: amanuensis and cf. "cellular, granular", for some speakers "virulent".
• After a consonant cluster /j/ may or may not be deleted: pæninsula, cornucopia

Closed u appears only in closed syllables, except for instances of the prefix sub- before a vowel. It has reduced and r-colored variants, as shown below. r-coloration only appears when the r is followed by a different consonant (not r) or the end of the word.

Diphthongs in Anglo-Latin are distinguished from simple vowels by having no long or short variants, regardless of position or syllable type. The only diphthongs that are at all common are au and eu. For variations in the pronunciation of the latter, see Open u. Au is, rarely, reduced in an unstressed syllable to [ə]: Augustus pronounced as if "Agustus". Such words may be pronounced with the full value of the diphthong, however.

Note that ui is generally disyllabic, as in fruc.tu.i, va.cu.i, tu.i. The monosyllabic words cui and huic were traditionally pronounced /kaɪ/ and /haɪk/.

The first class consists of vowels alone, i.e. -a, -e, -æ, -i, -o, -u, -y. In this class, the vowels are generally long, but -a is always /ə/.[6]

Words deriving from Greek long -ê (η) end in /iː/ unless assimilated, such as simile ending in /i/ (the 'HAPPY' vowel).

In the words mihi , tibi, sibi, by an old tradition, the final i was pronounced like final e above (i.e., as if spelled mihe, tibe, sibe).

A late and purely academic pronunciation distinguished final -ā from -a by pronouncing the former like "long a", /eɪ/: for instance, Oxford professor A. D. Godley rhymed Rusticā and "day". That this was not the usual pronunciation can be told from such forms as circa, infra, extra, in absentia, sub pœna, all of which have an originally long final vowel: circā, sub pœnā, etc. This use is distinct from the older tradition (in use in the 17th-18th centuries) had made all final a's "long", regardless of their Latin length.

The second class consists of vowels followed by consonant clusters such as ns, nt, nx, ps, x. In this class, the vowels are always short, except for u, which may be reduced to [ə].

The third class consists of vowels followed by the consonants l, m, n, r, s, t. The treatment of these endings is inconsistent. Generalizations include:

1. All vowels are reduced before final r for /ər/: Cæsar, pauper, triumvir, Mentor, sulfur, martyr.
2. All vowels are reduced to /ə/ before l: tribunal, Babel, pugil, consul.
3. Except sometimes before t, a is reduced to /ə/ before any of this class of consonant: animal, memoriam, titan, atlas.
4. All instances of u are reduced to /ə/ before any of this class of consonant: consul, dictum, locus.

The remaining endings are: -at, -em, -en, -es, -et, -im, -is, -it, -on, -os, -ot. Of these, -em, -im, -is, -it, -on, -ot have two possible pronunciations, one with a short vowel and one with /ə/. Final -es and -ies are alike pronounced /iːz/.[7] Final -eus, when derived from Greek -ευς -eus (as in Proteus) rather than from -εος -eos with the -os changed to -us in Latin, may be pronounced as a single syllable with a diphthong (juːs), or as two syllables with a long (though unstressed) e followed by -us (iː.əs). However, even when pronounced as two syllables, -eus counts as a single syllable for the purpose of determining vowel length – that is, the syllable preceding the -eus ending is considered the penult, just as happens in derivatives ending in -ian – though the placement of the stress shifts. E.g. Ἰλιονεύς Īlioneus /ɪliˈoʊniːəs, ɪˈlaɪənjuːs/ il-i-OH-nee-us, i-LY-ə-nyoos.

* The vowel of -is, -it is a "schwi". It generally conflates with /ɪ/ in RP and with schwa in Australia.

This last pronunciation of -os is the expected one; however, in the masculine accusative plural, where the ending is historically -ōs, the academic prescription was the pronunciation /oʊs/.[8] Such an ending is not found in English loan words or proper names.

English adjectives formed from Greek and Latin roots often end in a suffix -an or -ic added to the oblique stem, sometimes retaining a preceding thematic vowel. These produce generally predictable sound changes in the stem though, depending on its source or simply due to confusion, English -ean may be either stressed or unstressed. The first derives from the Latin adjectival suffix -ānus, though it has far wider application in English than in Latin. (Pythian, for example, translates the Latin adjective Pythius.) The other suffix, -ic, derives from the Greek adjectival suffix -ικος -ĭkos.[9]

The fact that these suffixes are added to the oblique stem is relevant with words of the third declension whose stems end in a consonant that alters or disappears in the nominative case, as is apparent in such English noun–adjective pairs as Pallas ~ Palladian, Mars ~ Martian, Venus ~ Venerian, and indeed from non-adjectival derivatives of these words such as 'palladium'. Some roots have more than one oblique stem, in which case they may have more than one adjectival form in English.

Stressed vowel plus -an and unstressed -ian

The forms of these suffixes depends on the first vowel of the nominal suffix in Latin or Greek. The resulting forms are carried over into Latin from Greek, and into English from Latin. English adjectives in -ean, where the e is inherited from the Greek, are stressed on the suffix, but there are also adjectives in -ean where the e originates in Latin, and those are not stressed.

For example,

• Greek Samos > adjective Samios > Latin Samius > English 'Sā́mian'
• Greek Periklēs > adjective Perikleios > Latin Periclēus > English 'Pericléan'
• Greek Lēda > adjective Lēdaios > Latin Lēdæus > English 'Ledaean' or 'Ledéan'
• Greek noun and adjective Ptolemaios > Latin Ptolemæus > English 'Ptolemaean'
• Greek Argō > adjective Argōos > Latin Argōus > English 'Argóan'
• Greek Sapphō > adjective Sapphōios > Latin Sapphōius > English 'Sapphóian'

Because the i of the suffix -ian makes an exception to the usual shortening of antepenultimate vowels, forms such as 'Samian' above are pronounced with a long stressed vowel.

Many Greek nouns ending in -o- take adjectives like those ending in -ē- instead, and some may take either form, in which case there may be two adjectives in English. An example is Sisyphus:[9]

• Greek Sīsyphos > adjective Sīsyphios > Latin Sīsyphius > English 'Sisýphian'
• (or, alternatively) > adjective Sīsypheios > Latin Sīsyphēus > English 'Sisyphéan'

In the opposite direction, ē-vowel Aristotelēs produces 'Aristotḗlian' alongside expected 'Aristoteléan'.

The final iota subscript in Greek feminine words ending in -ῳ -ōi is frequently omitted in Latin, – if an 'i' appears in English it may be taken directly from the Greek, – but words that end in plain -ω -ō in Greek may also have Greek adjectives in -ōios if the 'i' was historically present.

Unstressed -ean

There is another suffix spelled -ean in English, but this one unstressed. It corresponds to the unstressed Latin adjectival suffix -ĕus and does not derive from Greek. An example is Latin Herculēs > Latin adj. Herculĕus > English 'Hercúlean', alongside Greek Hēraklēs > Greek adj. Hērakleios > Latin Hēraclēus/Hēraclīus > English 'Heracléan'. The stress assignment of the 'Herculean' has been affected by 'Heraclean' (or perhaps simply by the ambiguity of having two suffixes spelled '-ean'), so the mixed form 'Herculéan' is now also heard.[10]

Adjectives in -ic

The Greek suffix -ικος -ĭkos replaces the vowels of nominal endings apart from retaining a or ō, which will be stressed in English. Stress assignment (and the corresponding vowel quality) of English follows the Latin, as though the suffix were -icus in English as well and the last syllable of the stem were the antepenult when it English it's actually the penult. Thus English 'Homeric' is pronounced with a short stressed penultimate e, when in other English words from Latin an e in that position would be pronounced long. (Cf. botanic, which has the same stressed 'a' and same vowel quality as botanical.)

For example,

• Greek Homēros > adjective Homērikos > Latin Homēricus > English 'Homĕ́ric'
• Greek Aristotelēs > adjective Aristotelikos > Latin Aristotelicus > English 'Arístotĕ́lic'
• Greek Alkaios > adjective Alkaikos > Latin Alcaicus > English 'Alcáic'
• Greek hērōs > adjective hērōikos > Latin hērōicus > English 'heróic'
• Greek ēchō > adjective ēchōikos > Latin ēchōicus > English 'echóic'

Thus 'Aristotelian' is pronounced with a long e, but 'Aristotelic' with a short e.

A number of Greek nouns ending in ē (which historically is a long ā) form adjectives in -aic, such as 'Cyrenaic' (Greek Kȳrēnē > adj. Kȳrēnaikos > Latin Cȳrēnaicus).

Latin from the period when its orthography and grammar became standardized through to the pronunciation changes of Late Latin, while it was still a living language. Changes that took place in this period included:

• the merger of f and ph as [f]
• the change in pronunciation of v (formerly [w]) to [v] and of j (formerly [j]) to [dʒ].
• the merger of i and y as [i]
• the merger of e, æ and œ as [e]
• the change of non-initial, unstressed, prevocalic [i] to [j]
• the loss of distinctions of vowel length (merger of all long and short vowels)
• the palatalization of t to [ts] before [j]

Latin spoken in the context of Gallo-Romance and French from approximately the 6th to the 11th-12th centuries. During this period, Latin became a primarily written language, separated from the ordinary spoken language of the people. While it escaped many of the changes of pronunciation and grammar of Gallo-Romance, it did share a few of the changes of the spoken language. This was for the most part a period of stability. Changes in this period included:

• the palatalization of c and g to [ts] and [dʒ] before front vowels
• the voicing of intervocalic s to [z]
• the fronting of u to [y]
• the restoration (based on spelling) of the vowels [i] and [e] from [j]

Latin spoken in the context of English from the 11th/12th centuries to the present. This last stage provides the greatest and most complicated number of changes. It starts with the displacement of the native pronunciation of Latin under the Anglo-Saxon kings with that used in the north of France, around the time of the Norman conquest in 1066. The English and French pronunciations of Latin were probably identical down to the 13th century, but subsequently Latin as spoken in England began to share in specifically English sound changes. Latin, thus naturalized, acquired a distinctly English sound, increasingly different from the pronunciation of Latin in France or elsewhere on the Continent.

Some phases of development in this third stage can be reconstructed:

• The adaptation of the French sounds to English:
  • [s] was substituted for [ts]. (The French sound changed at about the same time; however, Anglo-Latin did not share related French simplifications such as [dʒ] > [ʒ].)
  • the vowels were given the values a [a], e [ɛ], i [i], o [ɔ], u [y]
  • [u] was substituted for [y] in closed syllables, eg lux [lyks] > [luks]. [y] did not substitute out as [u] in unstressed open syllables, as it would have if the [y]~[u] distinction was solely length based: saeculum [sɛkylum]
  • At some point in the Middle English period, the distinctly French vowel [y] was substituted with the English diphthong [iw]. It is unclear when exactly this happened, and may have always been the English pronunciation of French (and consequently Latin) u.
• Stressed open penultimate vowels were lengthened, creating the short/long contrasts:

a [a]:[aː], e (also ae, oe) [ɛ]:[ɛː], i (also y) [i]:[iː], o [ɔ]:[ɔː], u [u] or [iw]:[iw]

• Merger of unstressed open [ɛ] with [ɪ]
• Non-syllable-initial, unstressed, prevocalic [ɪ] became [j] (a change almost identical to that of Late Latin)
• Lengthening of the first of two vowels in hiatus
• Lengthening of e [ɛ], i [ɪ], or o [ɔ] in pretonic initial syllables
• Diphthongization of [iː] to [ɛi]
• Lengthening of vowels in open syllables before [j] in the next syllable
• Raising of [ɛː] and [ɔː] to [eː] and [oː].
• Degemination of geminate consonants
• Palatalization of [s] and [z] before [j]
• Fronting of [ɐː] to [aː]

• Monophthongization of ai to [aː] and au to [ɔː]
• Change of [j] to [ɪ] (later > [i]) in many words, restoring original syllabicity.
• Change of fronted u ([iw]) to [juː]
• Palatalization of [t d s z] before (usually unstressed) [juː] (later > [jə])
• Lowering (and unrounding in the case of [ʊ]) of short [ʊ], [ɔ] to [ʌ], [ɒ]
• Tensing of short e [ɛ] to [e]
• Former long i [ɛi] becomes [ai]
• Fronting and raising of short a [a], long a [aː], and long e [eː] to [æ] [eː] [iː], creating the new contrasts: a [æ]: [eː], e [e]:[iː], i [ɪ]:[ai], o [ɒ]:[oː]
• Beginning of vowel reductions to [ə].
• Short e, i and u before R; i.e. [ɛɹ], [ɪɹ] and [ʌɹ] are all merged to [ɜɹ]. (the NURSE merger)
• Short a [æ] is lowered and lengthened before r in a closed syllable, ultimately reaching modern [ɑː]

• Development of [eː] and [oː] to diphthongs [ei] and [ou]
• Laxing of [ei] [ou] to [eɪ] {{IPA|[oʊ]}, and the latter to [əʊ]
• In syllable final position, r [ɹ] becomes a vowel [ə̯] (non-rhoticity). The vowel-R sequences simplify somewhat: arC [ɑə̯] > [ɑː], orC [ɒə̯] > [ɔː], erC, irC, urC [ɜə] > [ɜː].
• Continued vowel reductions to [ə] (an obsolete process).
• Shortening of a in a stressed open penult syllable, e.g., data. (not for all speakers)

• Reduction of [ɪ] and [ə] in words with free variation between the two vowels to [ɨ]