gamer (n.) Look up gamer at Dictionary.com
1620s, "an athlete," agent noun from game (v.). Meaning "one devoted to playing video or computer games" is attested from 1999. Gamester is attested from 1590s but meant "prostitute" (cf. old slang the first game ever played "copulation"), later "a man fit and ready for anything, a player" (mid-17c.).