Turkish phonology

A notable feature of Turkish phonology is a system of vowel harmony that causes vowels in most words to be either front or back and either rounded or unrounded. Stop consonants have palatal allophones before front vowels and velar allophones before back vowels.

In native Turkic words, the velar consonants /k, ɡ/ are palatalized to [c, ɟ] (similar to Russian) when adjacent to the front vowels /e, i, ø, y/. Similarly, the consonant /l/ is realized as a clear or light [l] next to front vowels (including word finally), and as a velarized [ɫ] next to the central and back vowels /a, ɯ, o, u/. These alternations are not indicated orthographically: the same letters ⟨k⟩, ⟨g⟩, and ⟨l⟩ are used for both pronunciations. In foreign borrowings and proper nouns, however, these distinct realizations of /k, ɡ, l/ are contrastive. In particular, [c, ɟ] and clear [l] are sometimes found in conjunction with the vowels [a] and [u]. This pronunciation can be indicated by adding a circumflex accent over the vowel: e.g. gâvur ('infidel'), mahkûm ('condemned'), lâzım ('necessary'), although this diacritic's usage has been increasingly archaic.

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