Near-close near-back rounded vowel

The near-close near-back rounded vowel, or near-high near-back rounded vowel, is a type of vowel sound, used in some spoken languages. The symbol in the International Phonetic Alphabet that represents this sound is ⟨ʊ⟩ (a Latin upsilon, sometimes informally referred to as "horseshoe U"). Prior to 1989, there was an alternate IPA symbol for this sound, ⟨ɷ⟩ (a closed small letter Latin 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, which was also the original symbol for the vowel used by the IPA in 1900.

The Handbook of the International Phonetic Association defines [ʊ] as a mid-centralized (lowered and centralized) close back rounded vowel (transcribed [u̽] or [ü̞]), and the current official IPA name of the vowel transcribed with the symbol ⟨ʊ⟩ is a near-close near-back rounded vowel.

However, some languages have a vowel that is somewhat lower than the canonical value of [ʊ], though it still fits the definition of a mid-centralized [u]. It occurs in some dialects of English (such as General American and Geordie), as well as some other languages (such as Maastrichtian Limburgish). It can be narrowly transcribed with [ʊ̞] (a lowered ⟨ʊ⟩), [o̟] (a fronted ⟨o⟩), or [ɵ̠] (a retracted ⟨ɵ⟩). For precision, this can be described as a close-mid near-back rounded vowel.

Additionally, in some languages (such as Bengali and Luxembourgish), as well as some dialects of English (such as Scottish), there is a fully back near-close rounded vowel (a sound between cardinal ⟨u⟩ and ⟨o⟩), which can be transcribed in IPA with [ʊ̠], [u̞] or [o̝]. For precision, this can be described as a near-close back rounded vowel, or near-high back rounded vowel.

Sometimes, especially in broad transcription, this vowel is transcribed with a simpler symbol ⟨u⟩, which technically represents the close back rounded vowel.