"chess opening in which a pawn is risked for advantage later," 1656,
gambett, from It.
gambetto, lit. "a tripping up" (as a trick in wrestling), from
gamba "leg," from L.L.
gamba (see
gambol). Applied to chess openings in Sp. in 1561 by Ruy Lopez, who traced it to the It. word, but the form in Sp. was generally
gambito which led to Fr.
gambit, which has infl. the Eng. spelling of the word. Broader sense of "opening move meant to gain advantage" is first recorded in Eng. 1855.