1. something that hits or strikes with force
Usage: informal
2. a person who hits or strikes something forcefully
Usage: informal

Examples

• The baseball coach used a heavy thwacker to hit practice balls.
• He’s quite a thwacker when it comes to chopping wood.
• The old thwacker made a loud noise when it hit the target.
• She grabbed the nearest thwacker to swat the fly.
• The carnival game featured a rubber thwacker for hitting targets.