1, n. Slang term for the head, specifically the top of the head when used in a headbutt. Obviously, it refers to the idea that if you punch with your knuckles, a headbutt uses one big knuckle.
2, v. To headbutt someone, aka "give 'em the big knuckle."
Did you see that? Zinedine Zidane just gave that dude the big knuckle!

Ooh, right to the face with the big knuckle! Looks like his skull knocked out a few of his opponent's teeth!

Good answer--that's using the big knuckle.
by Talmanes December 21, 2006
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