| Noun | 1. | fastball - (baseball) a pitch thrown with maximum velocity; "he swung late on the fastball"; "he showed batters nothing but smoke"pitch, delivery - (baseball) the throwing of a baseball by a pitcher to a batter slider - a fastball that curves slightly away from the side from which it was thrown baseball, baseball game, ball - a ball game played with a bat and ball between two teams of 9 players; teams take turns at bat trying to score run; "he played baseball in high school"; "there was a baseball game on every empy lot"; "there was a desire for National League ball in the area"; "play ball!" | |