A twin is one of two offspring produced in the same pregnancy.

Twin may also refer to: Twin, Alabama, a city in the United States Twin, Belgium, Walloon name of the Belgium city of Thuin Twin (production team), a Swedish record production and songwriting team Twin (TV series), a Norwegian television crime drama series from 2019 Twin (windowing system), a windowing environment for text mode displays "Twin (song)", a song by Roddy Ricch featuring Lil Durk "Twin", a song from the album Ruby by Jennie Twin pattern, a software design pattern Willows TWIN, a Windows emulator Twin, a member of the Minnesota Twins baseball team Flat-twin engine V-twin engine Straight-twin engine, also referred to as a parallel-twin Crystal twin, a crystal sample with two domains containing a twin boundary Twin house, semi-detached housing Twin towns and sister cities, towns and cities involved in town twinning Gemini Twin, an American two-seat powered parachute design Air Creation Twin, a French two seat ultralight trike design

Surname Peter J. Twin (born 1937), English nuclear physicist

See also Twin paradox, a thought experiment Twin prime, a type of prime number Twin Range, a mountain range in the U.S. state of New Hampshire Twin Cone, a volcanic cone in British Columbia, Canada Twinning (disambiguation) Twins (disambiguation) The Twin (disambiguation) Twin Sisters (disambiguation) Gemini (disambiguation)