A normal to mildly attractive looking girl who has spent so much time with a DUFF she has taken on DUFF qualities (i.e. sitting around on her ass all the time, extreme sarcasm, increased appetite, and bitchiness). Occasionally refered to as a DUFF Ass.
"Dude, that girl was pretty nice when I got here, but now she's a total DUFF Associate. I'm gonna bang her friend instead."
A word used to describe a person or action that is DUFF related. It is often used in cases of extreme gluttony, cock blocking, being a fat bitch, being an ugly bitch, and/or being a fat and ugly bitch. NOTE: One does not necessarily have to be a DUFF for this word to apply to them.
"Miranda, you cockblocked Mark from getting to that hot chick over there? That was a pretty DUFFy move."