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 term is derived from the bully in Back to the Future I and II who harassed George McFly not only in has past, but also through the future.
YoMcFly, why don't you make like a tree and get outta here.
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."
A man with big hands. And an even bigger heart. Often Canadian, Tanne is a man who likes basketball.
You should be grateful if you ever come across a Tanne. But lookout, he will steal your bitches. He's a player.
All the girls simp for Tanne and his hot boy shorts. Tanne is life.
Lou: "give me some Tanne"
Random guy: "Tanne is a carrot"
Research Tangent: digressing suddenly from one topic of discussion to run to the nearest internet source in order to thoroughly research information either to: (A) reinforce a particular point or (B) attempt to relieve oneself from ignorance. Can be either directly or indirectly relevant.
... a trend that is sweeping the nation! Because knowledge is power!
Example: She totally went off on a research tangent in the middle of a movie last night when she wasn’t sure if sodium thiopental was the same as sodium pentothal.