U (disambiguation)

U is the twenty-first letter of the Latin alphabet.

U may also refer to:

Mathematics

* $cup$, union (set theory)
* U-set, a set of uniqueness
* U, the unitary group

Chemistry

* Uranium, a metallic chemical element
* Unified atomic mass unit, used to express atomic and molecular masses

Astronomy

* U, ultraviolet magnitude, in a UBV photometric system
* U, an October 16 through 31 discovery in the provisional designation of a comet

Computing

* , a now-deprecated HTML element denoting underlined text
* U, measurement of size of a rack unit
* U, Universal Turing machine

Other scientific uses

* U, the middle of an edge joining a hexagonal and a square face of the Brillouin zone of a face-centered cubic lattice, in solid-state physics
* U, one of the two subcarrier-modulated color-difference channels in the YUV colorspace, in video
* U, the recommended symbol for a system's internal energy, in thermodynamics

Music

* "U" (album), a double album by the Incredible String Band, released in 1970
* "U" (song), a song by Pearl Jam, released in 1998
* "U" (Super Junior song), a single by Super Junior, released in 2006
* "U", a song by S.E.S. (group), released in 2002

Education

* University, commonly abbreviated "U"
* U, an unsatisfactory grade, or 'Unclassified' (UK)

Other uses

* U (kana), a Japanese syllabary symbol
* U of Goryeo (1363-1389), king of Goryeo (Korea), often called King Woo
* U and non-U English, classes of language usage
*, hechsher or kosher certification by the Orthodox Union
* U (Universal), a film rating used by the British Board of Film Classification and, in India, the Central Board of Film Certification
* U, the color blue in ""
* U-, a prefix used for German submarines during World War II
* La U or Universitario de Deportes, a Peruvian soccer team
* U Mobile, Malaysian mobile phone and data service provider
* U-bend, a U-shaped plumbing trap
* Universitatea Cluj, a Romanian football club

ee also

* You (disambiguation)
* The U (disambiguation)

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