The OED defines mullet as ‘A hairstyle, worn esp. by men, in which the hair is cut short at the front and sides, and left long at the back.’ It was certainly popularized, if not coined, by the hip-hop group the Beastie Boys, whose song ‘Mullet Head’ is the first known use of the term:
You wanna know what’s a mullet? Well I got a little story to tell About a hair style, that’s way of life.
1994 Beastie Boys Mullet Head (song)
It is often claimed that the term derives from mullet-head, a colloquial reference to a stupid person. But a 1995 article in Grand Royal, a magazine published by the Beastie Boys, proposes several other, largely humorous origins, including a relationship with the mullet fish.
Can you help find an earlier example of mullet? Or any proof that it truly was coined by the Beasties?
http://public.oed.com/appeals/mullet/