Û, û (u-circumflex) is a letter of the Latin script.^[1]

This letter is used in some standards of Cyrillic transliteration as the letter Ю:

• GOST 16876-71 table 1
• ISO 9 (ISO 9:1986 and ISO 9:1995)

It is used in Wade-Giles (one of the romanization systems in Chinese) for apical dental unrounded vowel as in tzû, tz'û, ssû, corresponds to present zi, ci, si in Pinyin respectively.

û represents うう in both Nihon-shiki and Kunrei-shiki romanization systems.

In Afrikaans, û is a punctuated form of u and a usage example includes "brûe". plural of "brug" (= bridge).

Û represents [uː] in Emilian dialects: in the Bolognese dialect, anvûd [aŋˈvuːd] means "nephews".

In French, û does not change the pronunciation of the letter u except in jeune "young", which is pronounced differently from jeûne "a fast". In some other words like mû, the circumflex has no disambiguating value; attempts have been made to abolish it in such words. See Circumflex in French. Û also often appears in words that used to have an "s" after the "u": the French word for August, août, used to be written aoust.

Û represents the sound /uː/.

Û is occasionally used to represent the sound /uː/ in words like fûr, a poetic contraction of furono (they were).

Û is used in Kurdish Kurmanji alphabet in the to represent a long close back rounded vowel /uː/.

In the Masovian dialect, û represents /ju:/.

Û indicates palatalization of the preceding consonant: "sükûnet" (quietness) is pronounced /sycuːˈnet/.

In Welsh, û is used to represent a long stressed u [ɨː] or [iː] when, without the circumflex, it would be pronounced as a short [ɨ] or [ɪ]: cytûn [kəˑtɨːn, kəˑtiːn] "agreed", bûm [bɨːm, biːm] "I was" as opposed to bum [bɨm, bɪm] "five" (soft-mutated prenominal form).

• Circumflex