1. a person or animal that butts with the head
Usage: informal; often used in sports or animal contexts
2. a fish with a large, hard head used for ramming or defense
Usage: ichthyology

Examples

• The ram was a notorious headbutter that charged at anything in its path.
• In soccer, he earned a reputation as a headbutter for his aggressive aerial play.
• The goat proved to be a stubborn headbutter, constantly ramming the fence.
• Some fish species are natural headbutters, using their skulls as weapons.
• The player was suspended for being a headbutter during the match.