Onion is the common name given to plants in the genus Allium.
Onion or Onions may also refer to:
Places Onion Creek (Texas) Onion River (disambiguation), various rivers in the United States
People Ken Onion (born 1963), American knifemaker Todd Bodine (b. 1964), NASCAR driver nicknamed "The Onion" Onions (surname)
Arts, entertainment, and media The Onion, an American digital media company and news satire organization Onion, the name of the Pikmin spaceship in Pikmin (series) Onion, the name of a character in the animated TV series Steven Universe Onion (album), an album by Shannon and the Clams Onion, a 2009 album by Mike McClure Onion, a titular character is the TV series Apple & Onion
Organizational structures Onion (Arendt), a philosophical metaphor representing the organization of totalitarianism Onion model, a kind of chart that shows the dependencies among parts of an organization or process
Computing and technology .onion, a pseudo-top-level domain host suffix Onion routing, an anonymous communication technique
Other uses Onion (horse), an American thoroughbred racehorse False sea onion "The Onion", a nickname for the main building of the Sepulveda Unitarian Universalist Society.