Definitions by Smigslovesyou101

D.U.F.F.

D-dumb
U-ugly
F-fat
F-friend

or

D-dumb
U-unreasonable
F-fuck
F-face

Go with it as you wish.

Snooki: "Oh my God. What a D.U.F.F.!"
Deena: "I know, right? Totally a duff."