|Close central rounded vowel|
The close central rounded vowel, or high central 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 ⟨?⟩, and the equivalent X-SAMPA symbol is
}. Both the symbol and the sound are commonly referred to as "barred u".
In most languages this rounded vowel is pronounced with protruded lips (endolabial). However, in a few cases the lips are compressed (exolabial).
Some languages feature the near-close central rounded vowel, which is slightly lower. It is most often transcribed in IPA with ⟨⟩ and ⟨⟩, but other transcriptions such as ⟨⟩ and ⟨⟩ are also possible. The symbol ⟨?⟩, a conflation of ⟨?⟩ and ⟨?⟩, is used as an unofficial extension of the IPA to represent this sound by a number of publications, such as Accents of English by John C. Wells. In the third edition of the Oxford English Dictionary, ⟨?⟩ represents free variation between /?/ and /?/.
The close central protruded vowel is typically transcribed in IPA simply as ⟨?⟩, and that is the convention used in this article. As there is no dedicated diacritic for protrusion in the IPA, symbol for the close central rounded vowel with an old diacritic for labialization, ⟨ ?⟩, can be used as an ad hoc symbol ⟨⟩ for the close central protruded vowel. Another possible transcription is ⟨⟩ or ⟨⟩ (a close central vowel modified by endolabialization), but this could be misread as a diphthong.
Because central rounded vowels are assumed to have protrusion, and few descriptions cover the distinction, some of the following may actually have compression.
|Angami||Khonoma||su||[s]||'deep'||Allophone of /u/ after /s/.|
|Armenian||Some Eastern dialects||??/yow?||[j]||'oil'||Allophone of /u/ after /j/.|
|Berber||Ayt Seghrouchen||/llayggur||[l:æj'?:]||'he goes'||Allophone of /u/ after velar consonants.|
|Dutch||Standard Northern||nu||[n?]||'now'||Typically transcribed in IPA with ⟨y⟩; also described as close front  and near-close front . See Dutch phonology|
|Randstad||hut||[t]||'hut'||Found in Amsterdam, Rotterdam and The Hague. Lower in Standard Dutch. See Dutch phonology|
|English||Australian||goose||[:s]||'goose'||See Australian English phonology|
|England||Can be back or front instead. The rounding is variable in some varieties.|
|New Zealand||See New Zealand English phonology|
|Received Pronunciation||Realized as back in the conservative variety.|
|South African||Realized as back in the conservative variety and in many Black and Indian varieties. See South African English phonology|
|General American||[s]||Can be back instead.|
|Estuary||foot||[ft]||'foot'||The exact height, backness and roundedness is variable.|
|Cockney||good||[d]||'good'||Only in some words, particularly good, otherwise realized as near-back .|
|Rural white Southern American||Can be front instead.|
|Southeastern English||May be unrounded instead; it corresponds to in other dialects. See English phonology|
|Ulster||Short allophone of /u/.|
|Shetland||strut||[stt]||'strut'||Can be or instead.|
|German||Upper Saxon||Buden||['b:d?n?]||'booths'||The example word is from the Chemnitz dialect.|
|Hausa||[example needed]||Allophone of /u/.|
|Ibibio||Dialect of the Uruan area and Uyo||fuuk||[fk]||'cover many things/times'||Allophone of /u/ between consonants.|
|Some dialects||[example needed]||Phonemic; contrasts with /u/.|
|Irish||Munster||ciúin||[c?:n?]||'quiet'||Allophone of /u/ between slender consonants. See Irish phonology|
|Ulster||úllaí||[?i][stress?]||'apples'||Often only weakly rounded; may be transcribed in IPA with ⟨u⟩.|
|Limburgish||Some dialects||bruudsje||['bt]||'breadroll'||Close [?] or near-close , depending on the dialect. Close front in other dialects. Typically transcribed in IPA with ⟨y⟩. The example word is from the Maastrichtian dialect, in which the vowel is close.|
|Russian||??/kyuriy/kjurij||['krj]||'curium'||Allophone of /u/ between palatalized consonants. Near-close when unstressed. See Russian phonology|
|Scots||buit||[b?t]||'boot'||May be more front instead.|
|Swedish||Bohuslän||yla||[²:lä]||'howl'||A fricated vowel that corresponds to in Central Standard Swedish. See Swedish phonology|
|Tamil||?/v?lu||[vä:l?]||'tail'||Epenthetic vowel inserted in colloquial speech after word-final liquids; can be unrounded instead. See Tamil phonology|
|Close central compressed vowel|
As there is no official diacritic for compression in the IPA, the centering diacritic is used with the front rounded vowel [y], which is normally compressed. Other possible transcriptions are ⟨?⟩ (simultaneous [?] and labial compression) and ⟨⟩ ([?] modified with labial compression).
This vowel is typically transcribed in IPA with ⟨?⟩. It occurs in some dialects of Swedish, but see also close front compressed vowel. The close back vowels of Norwegian and Swedish are also compressed. See close back compressed vowel. It also occurs in Japanese as an allophone. Medumba has a compressed central vowel  where the corners of the mouth are not drawn together.
|Japanese||Some younger speakers||/ k?ki||[kÿ:ki]||'air'||Near-back for other speakers.|
|Standard Tokyo pronunciation||/ sushi||[sÿ?i]||'sushi'||Allophone of /u/ after /s, z, t/ and palatalized consonants. See Japanese phonology|
|Norwegian||Urban East||hus||[hÿ:s]||'house'||Typically transcribed in IPA with ⟨?:⟩. Also described as front . See Norwegian phonology|
|Swedish||Some dialects||ful||[fÿ:l]||'ugly'||More front [y: ~ ?:] in Central Standard Swedish; typically transcribed in IPA as ⟨?:⟩. See Swedish phonology|