'ballplayer' originates from Modern English as a compound of 'ball' + 'player', where 'ball' refers to a spherical object used in games and 'player' means 'one who plays'.

'ballplayer' developed in the late 19th to early 20th century as organized team sports (especially baseball) grew in popularity in the United States; it likely shortened from phrases such as 'baseball player' to the compound 'ballplayer'.

Initially used chiefly to refer to a 'baseball player' (especially professional players), it has sometimes broadened to refer informally to players of other ball games.