Vowel diagram illustrating the /i–ɪ̟–e/ and /u–ʊ̠–o/ contrasts in Sotho, from Doke & Mofokeng (1974:?). The near-close vowels are normally transcribed without diacritics (i.e. as ⟨ɪ⟩ and ⟨ʊ⟩, respectively), or even with the symbols for close central vowels (⟨ɨ⟩ and ⟨ʉ⟩, respectively), though the latter set is not phonetically correct.
A near-close vowel or a near-high vowel is any in a class of vowel sound used in some spoken languages. The defining characteristic of a near-close vowel is that the tongue is positioned similarly to a close vowel, but slightly less constricted.
Other names for a near-close vowel are lowered close vowel and raised close-mid vowel, though the former phrase may also be used to describe a vowel that is as low as close-mid (sometimes even lower); likewise, the latter phrase may also be used to describe a vowel that is as high as close.
Near-close vowels are also sometimes described as lax variants of the fully close vowels, though, depending on the language, they may not necessarily be variants of close vowels at all.
It is rare for languages to contrast a near-close vowel with a close vowel and a close-mid vowel based on height alone. An example of such language is Danish, which contrasts short and long versions of the close front unrounded /i/, near-close front unrounded /e̝/ and close-mid front unrounded /e/ vowels, though in order to avoid using any relative articulation diacritics, Danish /e̝/ and /e/ are typically transcribed with phonetically inaccurate symbols /e/ and /ɛ/, respectively.[1] This contrast is not present in Conservative Danish, which realizes the latter two vowels as, respectively, close-mid [e] and mid[e̞].[2]
It is even rarer for languages to contrast more than one close/near-close/close-mid triplet. For instance, Sotho has two such triplets: fully front /i–ɪ–e/ and fully back /u–ʊ–o/.[3] In the case of this language, the near-close vowels /ɪ,ʊ/ tend to be transcribed with the phonetically inaccurate symbols /ɨ,ʉ/, i.e. as if they were close central.
It may be somewhat more common for languages to contain allophonic vowel triplets that are not contrastive; for instance, Russian has one such triplet:[4]
close central rounded [ʉ], an allophone of /u/ between soft consonants in stressed syllables;
near-close central rounded [ʉ̞], an allophone of /u/ between soft consonants in unstressed syllables;
close-mid central rounded [ɵ], an allophone of /o/ after soft consonants.
The Handbook of the International Phonetic Association defines these vowels as mid-centralized (lowered and centralized) equivalents of, respectively, [i], [y] and [u],[5] therefore, an alternative transcription of these vowels is [i̽,y̽,u̽] or the more complex [ï̞,ÿ˕,ü̞]; however, they are not centralized in all languages - some languages have a fully front variant of [ɪ] and/or a fully back variant of [ʊ];[6] the exact backness of these variants can be transcribed in the IPA with [ɪ̟,ʊ̠], [i̞,u̞] or [e̝,o̝].
There also are near-close vowels that don't have dedicated symbols in the IPA:
(IPA letters for rounded vowels are ambiguous as to whether the rounding is protrusion or compression. However, transcription of the world's languages tends to pattern as above.)
Other near-close vowels can be indicated with diacritics of relative articulation applied to letters for neighboring vowels, such as ⟨ɪ̟⟩, ⟨i̞⟩ or ⟨e̝⟩ for a near-close front unrounded vowel, or ⟨ʊ̠⟩, ⟨u̞⟩ or ⟨o̝⟩ for a near-close back rounded vowel.
Doke, Clement Martyn; Mofokeng, S. Machabe (1974), Textbook of Southern Sotho Grammar (3rd ed.), Cape Town: Longman Southern Africa, ISBN0-582-61700-6
International Phonetic Association (1999), Handbook of the International Phonetic Association: A guide to the use of the International Phonetic Alphabet, Cambridge: Cambridge University Press, ISBN0-521-65236-7
Jones, Daniel; Ward, Dennis (1969), The Phonetics of Russian, Cambridge University Press, ISBN0-521-06736-7
