The symbol in the International Phonetic Alphabet that represents this sound is ⟨ɨ⟩, namely the lower-case letter i with a horizontal bar.

[2] The close central unrounded vowel is the vocalic equivalent of the rare post-palatal approximant [j̈].

However, it is very common as a separate phoneme in the indigenous languages of the Americas and is often in phonemic contrast with other close vowels such as /i/ and /u/ both in modern living languages as well as reconstructed proto-languages (such as Proto-Uto-Aztecan).

[6] The sound of Polish ⟨y⟩ is often represented as /ɨ/, but actually it is a close-mid advanced central unrounded vowel, more narrowly transcribed [ɘ̟].

[63] Similarly, European Portuguese unstressed ⟨e⟩, often represented as /ɨ/, is actually a near-close near-back unrounded vowel,[64] more narrowly transcribed using ad hoc symbols such as [ɯ̽] (mid-centralized), [ɯ̟] (fronted) and [ʊ̜] (less rounded, i.e. unrounded).