Definition of "gaslight" in English

noun

1. A lamp which operates by burning piped illuminating gas (or town gas).

2. (uncountable) The light produced by the burning gas in such a lamp.

verb

1. (formal, strictly, prescriptive) To manipulate someone such that they doubt their own memory, perceptions of reality, or sanity, typically for malevolent reasons.

   • Sylvia is a beautiful woman whose business-partner husband is "gaslighting" her. (That means he's trying to drive her crazy.)
   • [The men of McHale's Navy] decide to "gaslight" the already befuddled captain, to convince him he is going insane.
   • "You're gaslighting me, for chrissakes."
   • 1967, Stan Freberg (comedian), on his "most excruciating experience with a producer" as interviewed in Humphrey, Hal. "'Dramatic' Role Played By Freberg." The Oregonian [Portland, OR]. February 11, 1967: II 3 col 3. I came home before he could gaslight me like Boyer did Bergman in the movie.
   • Just in the nick of time Rachel finds out the truth about her life from Martha. … This is how I wanted to show the gaslighting that had been going on Rachel's entire life.

2. (loosely, informal, proscribed) To deceive, trick, or lie to.