1) An athlete, a player at games, a gambler, often used pejoratively.
1602 dronkerds, gaymsters, stealers of wodd & connyes, brablers, Brandsby
1607-8 Geo. Davison of Scruton, butcher, for that he is a gamester at cardes and doth waist his estate thereby
1735 John Firth gamester. Lent him at Nich. Bramalds to play at Cards with 10s 6d, Huddersfield. It was used as a name for some animals: 1598-9 two red oxen Gamster and Guyde, Scruton: also the name of a hound: 1697 of gamster from Phixby, Woodsome.