Headbanger (noun)

1. A person who moves their head rhythmically to the beat of music, especially heavy metal.
2. A fan of heavy metal music who is known for physically expressing their enjoyment of the music, often by violently shaking their head.

Origin:

The term is derived from the physical gesture of repeatedly striking one's head, often in time with the music, and it is commonly associated with heavy metal music.

Examples:

1. The concert was full of headbangers, all thrashing their heads to the music.
2. He was known as a headbanger and was often seen at concerts with a bandana tied around his head.
3. The crowd was full of headbangers, moshing and jumping to the music.
4. The headbanger's wild head movements made him look as if he was having a seizure.
5. The headbanger's enthusiasm for the music was contagious, soon everyone was headbanging.