gaslight · noun1
From gas (“flammable gaseous hydrocarbon or hydrocarbon mixture used as a fuel”) + light.
gaslight · verb2
From the 1938 stage play Gas Light by the English playwright and novelist Patrick Hamilton (1904–1962), and its 1940 and 1944 film adaptations, in which a husband attempts to convince his wife and others that she is insane by manipulating small elements of their environment. For more details, see also Gaslighting § Etymology on Wikipedia.
Etymology from Wiktionary, CC BY-SA 4.0.