noun
- an act or instance of selling out.
- an entertainment, as a show or athletic event, for which all the seats are sold.
- Informal. a person who betrays a cause, organization, or the like; traitor.
- Informal. a person who compromises his or her personal values, integrity, talent, or the like, for money or personal advancement.
n.also sell-out, “corrupt bargain,” 1862 (in Mary Chesnut’s diary), from the verbal phrase (at that time often meaning “dispose of one’s interests” in a company, etc.), from sell (v.) + out (adv.). Meaning “event for which all tickets have been sold” is attested from 1923. The verbal phrase sell out “prostitute one’s ideals or talents” is attested from 1888.