A mullet is any of a number of fish in the family Mullidae and especially the genus Mullus. Mullets are found in both fresh and salt water. Mullets have been an important food in Mediterranean Europe since Roman times.
A mullet is a type of haircut, long associated with United States redneck culture. It is short on top, long (shoulder length or more) in back, and very often combined with a moustache. The term was purportedly coined by the Beastie Boys.
Mullet is slang for a person that mindlessly follows a fad, trend, or leader.