For the Cyrillic letter Ї, see Yi (Cyrillic)
. For the homographic Greek letter, see ϊ
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—that is, 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 (IPA: [ukrɑːˈinə], Ukraine), and English naïve (// or //).
In scholarly writing on Turkish, 〈ï〉 is sometimes used to write the close back unrounded vowel /ɯ/, which in standard modern Turkish orthography is written as the dotless i 〈ı〉.
In the transcription of the languages of the Amazon, ï is used to represent the high central vowel [ɨ].