Gaslighting is used to describe abusive behavior, specifically when an abuser manipulates information in such a way as to make a victim question his or her sanity. Gaslighting intentionally makes someone doubt their memories or perception of reality.

The term Gaslighting originates in the systematic psychological manipulation of a victim by her husband in Patrick Hamilton’s 1938 stage play Gaslight, and the film adaptations released in 1940 and 1944. In the story, the husband attempts to convince his wife and others that she is insane by manipulating small elements of their environment and insisting that she is mistaken, remembering things incorrectly, or delusional when she points out these changes. The play’s title alludes to how the abusive husband slowly dims the gas lights in their home, while pretending nothing has changed, in an effort to make his wife doubt her own perceptions. The wife repeatedly asks her husband to confirm her perceptions about the dimming lights, but in defiance of reality, he keeps insisting that the lights are the same and instead it is she who is going insane.