doublecrossed

Doublecrossed, or double-crossed, is a term used to describe the act of betraying someone who had trusted you, typically by feigning loyalty and then aiding an opponent or pursuing your own interests. In everyday usage, a person who is double-crossed is betrayed after an initial agreement or partnership.

Etymology and usage: The phrase derives from cross in the sense of deception. The prefix double- emphasizes a second crossing or a second party involved. It has appeared in English crime and espionage slang since the early 20th century. In the context of espionage, the term is closely associated with the Double-Cross System, the British counter-espionage network in World War II that used carefully managed doubles to feed false information to the Germans.

In popular culture: Doublecrossed or Double-Crossed is used as a plot device in crime fiction, thrillers, and heist narratives, and appears as a title or subtitle in various books, films, or TV episodes.

See also: double-cross; betrayal; trust; espionage; heist fiction.