Ï

Ï, lowercase ï, is a symbol used in various languages written with the Latin alphabet; it can be read as the letter I with diaeresis or I-umlaut.

In Afrikaans, Catalan, Dutch, French, Galician, Welsh, Southern Sami, and occasionally English, ⟨ï⟩ is used when ⟨i⟩ follows another vowel and indicates hiatus (diaeresis) in the pronunciation of such a word. It indicates that the two vowels are pronounced in separate syllables, rather than together as a diphthong or digraph. For example, French maïs (IPA: [ma.is], maize); without the diaeresis, the ⟨i⟩ is part of the digraph ⟨ai⟩: mais (IPA: [mɛ], but). The letter is also in Dutch Oekraïne (pronounced [ukraːˈinə], Ukraine), and English naïve (/nɑːˈiːv/ or /naɪˈiːv/).

In German and Hungarian, ï does not belong to the alphabet.

In scholarly writing on Turkic languages, ⟨ï⟩ is sometimes used to write the close back unrounded vowel /ɯ/, which, in the standard modern Turkish alphabet, is written as the dotless i ⟨ı⟩.[1] The back neutral vowel reconstructed in Proto-Mongolic is sometimes written ⟨ï⟩.[2]

In the transcription of Amazonian languages, ï is used to represent the high central vowel [ɨ].

It is also a transliteration of the rune ᛇ.