Nut loaf with sausage

• Heavy metal fan
• Heavy metal rock fan
• Heavy metal enthusiast

Douglas Harper's Etymology Dictionary Word definitions in Douglas Harper's Etymology Dictionary
"devotee of heavy metal music," 1984, from head (n.) + agent noun from bang (v.).

Wikipedia Word definitions in Wikipedia
A Headbanger is a slang term for a fan of heavy metal music Headbanger or Headbangers may also refer to:

Longman Dictionary of Contemporary English Word definitions in Longman Dictionary of Contemporary English
noun EXAMPLES FROM CORPUS ▪ It all led to only two possibilities: he was either a whirling business genius or a complete headbanger .

Wiktionary Word definitions in Wiktionary
n. 1 One who dances by violently shaking the head in time to the music. 2 (context by extension English) one who enjoys heavy metal rock music, to which this sort of dance is usually performed. 3 A mad or eccentric person.