1. a fan of heavy metal music, especially one who dances by vigorously shaking the head up and down
Usage: informal; often used in music culture
2. a person who repeatedly hits their head against something, or engages in self-injurious head-banging behavior
Usage: medical or behavioral context

Examples

• The concert was packed with headbangers enjoying the heavy metal performance.
• She's been a headbanger since the 1980s and still loves attending rock shows.
• The crowd of headbangers moved in unison to the driving beat of the drums.
• Some headbangers at the festival wore leather jackets and band t-shirts.
• The pediatrician explained that occasional head-banging in toddlers is common, though persistent headbanging may need evaluation.