1. a baseball pitcher who specializes in throwing fastballs; a pitcher known for throwing hard, fast pitches
Usage: informal; sports

Examples

• The young fastballer impressed scouts with his 95-mph fastball.
• He's a pure fastballer who relies on speed rather than breaking balls.
• The team signed the fastballer to a long-term contract.
• As a fastballer, she dominated the league with her velocity.
• The fastballer threw three consecutive strikes to end the inning.