"A creature without many cells. He was one of those big lizards that never feels any pain when you rip off its tail, or one of its legs--or even its head, as they do down in Chile---because it will all grow back by dawn, and nobody with know the difference."
Hunter S. Thompson liked to use this word to describe stupid locals that he ran into during his travels and misadventures around Key West and Cuba. Only in one of his writings does he actually define the term. This quote is from <i>Generation of Swine<i>.
"That dumb fishhead waitress has an IQ of 58, she fucked up my order for the fifth time."
"Hey, that fucking fishhead bum just jacked my slice of pizza!!"