# U (disambiguation)

Not to be confused with Ս.

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

U may also refer to:

## Science

### Astronomy

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

### Other scientific uses

• U, a common notation for potential energy
• 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
• U, units, any of various standard units of biological activity, such as insulin units, enzyme units, or penicillin units
• U, the abbreviation for selenocysteine, an uncommon amino acid containing selenium
• u, the alternative abbreviation for the SI prefix "micro-" when the Greek letter mu (µ) is not available

## People

• An honorific used in Burmese names
• An alternative spelling of Woo (Korean name), including a list of people with that family or given name
• U of Goryeo (1363–1389), king of Goryeo (Korea), often called King Woo

## Education

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

## Film and television

• U (film), a 2006 French animated feature film directed by Serge Elissalde and Grégoire Solotareff
• The U (film), a 2009 documentary about the Miami Hurricanes football team
• U (Universal), a film rating used by:
• U (TV channel), a former television channel in New Zealand