U-, a prefix used for German submarines during World War II

U, an unsatisfactory grade, or 'Ungraded' (UK)

Uranium, a metallic chemical element

U, the color blue in Magic: The Gathering

U (honorific), an honorific title in Burmese society, such as U Nu

<u>, a deprecated HTML element denoting underlined text

University, commonly abbreviated "U"

La U or Universitario de Deportes, a Peruvian soccer team

"U", a song by S.E.S. (group), released in 2002

U, one of the two subcarrier-modulated color-difference channels in the YUV colorspace, in video

U, the unitary group

U, the recommended symbol for a system's internal energy, in thermodynamics

U-set, a set of uniqueness

<math>\cup</math>, union (set theory)

Unified atomic mass unit, used to express atomic and molecular masses

"U" (Super Junior song), CD single released in 2006

U Mobile, Malaysian mobile phone and data service provider

U and non-U English, classes of language usage

"U" (song), a song by Pearl Jam, released in 1998

U of Goryeo (1363-1389), king of Goryeo (Korea), often called King Woo

U (kana), a Japanese syllabary symbol

Ⓤ, hechsher or kosher certification by the Orthodox Union

U is the twenty-first letter of the Latin alphabet. U may also refer to:

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-bend, a U-shaped plumbing trap

U (album), a double album by the Incredible String Band, released in 1970

You (disambiguation)

U, measurement of size of a rack unit

U, ultraviolet magnitude, in a UBV photometric system

The U (disambiguation)

U (Universal), a film rating used by the British Board of Film Classification and, in India, the Central Board of Film Certification

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