A quick tempered, slow witted jock, often in the context of a bully. A Biff often compensates for his lack of knowledge with force or otherwise aggressive action.
The sexual maneuver in which a man uses the head of his erect penis to vigorously knock three times on his partner's forehead and then exclaim "Hello?! McFly?!", in reference to Back to the Future Part II.
"I Biff Tannen'd her so hard I put a dent in her skull and now there's blood when I urinate."
