The near-close near-back vowel, or near-high near-back vowel, is a type of vowel sound, used in some vocal languages. The IPA symbol for the near-close near-back rounded vowel is ⟨ʊ⟩. It is informally called "horseshoe u". Prior to 1989, there was an alternate IPA symbol for this sound, ⟨ɷ⟩, called "closed omega"; use of this symbol is no longer sanctioned by the IPA. In Americanist phonetic notation, the symbol ⟨ᴜ⟩ (a small capital U) is used.
The IPA prefers the terms "close" and "open" for vowels, and the name of the article follows this. However, a large number of linguists, perhaps a majority, prefer the terms "high" and "low".
Some languages may have a near-close near-back unrounded vowel, which can be represented with ⟨ɯ̽⟩ or ⟨ʊ̜⟩ in the IPA, or sometimes with the old convention of ⟨ω⟩.[1] A near-close near-back compressed vowel can be transcribed ⟨ʊᵝ⟩.
Its vowel backness is near-back, also known as back-central or centralized back, which means the tongue is positioned as in a back vowel, but slightly further forward in the mouth.
It's rounded, which means that the lips are rounded rather than spread or relaxed.
The near-close near-back unrounded vowel does not occur very often in world's languages, and the only languages in which it is phonemic are Korean and Portuguese (the European variety).
Its vowel backness is near-back, also known as back-central or centralized back, which means the tongue is positioned as in a back vowel, but slightly further forward in the mouth.
It is unrounded, which means that the lips are not rounded.
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