D.U.F. 

Meaning, "Designated Ugly friend."

A pretty girl always has pretty friends, but when she wants to snag guys, she brings along her D.U.F. only.
So who is the guys going to hit on?

You get the picture.

D.U.F. by Cheyenne Low October 18, 2008

D.U.F.F. 

An abbreviation for 'Designated Ugly Fat Friend'. Often in many large groups of women (usually adolecents) there will be a D.U.F.F. as a means to look better by comparison.

I only hang out with her becuase I need a D.U.F.F., otherwise, she'd be, so, history.

D.U.F.F. by B.a.m December 21, 2005

D.U.F.F. 

The Designated (/Dumb) Ugly Fat Friend.

The cock-blocking friend of the hot chick you're trying to hook up with, often the target of the wingman.

I was totally in with this chick and then her D.U.F.F. totally cock-blocked me!

-or-

I'll take her, while you distract her D.U.F.F.!

D.U.F.F. by Victory2FuManchu September 7, 2006

D.U.F.A 

Designated Ugly Fat Ass

Ew look at that D.U.F.A

D.U.F.A by J.D.R August 25, 2009

D.U.F.F 

D.U.F.F stands for designated ugly fat friend

Kassie wants to feel good about herself so she has a D.U.F.F

D.U.F.F by Nick November 22, 2004

D.U.F.F 

Literally stands for Designated Ugly Fat Friend. This is the bitch who comes out of no where to cockblock you when you are about to get a chick home with you. She is often recognizable by her fat ass, bad hair and sour disposition. Her main goal of the night is to fend off any advances on her friend so she will have company at the diner when she is stuffing her fat face with an omelet and a side of disco fries while she bitches about anyone and everyone. The D.U.F.F can be defeated with a high level wingman, but you will be expected to return the favor; a job not for the faint of heart. A naked D.U.F.F often smells like a box of crayons.

"Dude, I was about to bag this chick, but then her army of D.U.F.F's came out of no where and pulled her away. She must be a Volleyball player!"

"Did you Fuck the chick at the party?"
"No Fuckhead, I got Duffed!"

D.U.F.F by LexDimonds July 31, 2009

D.U.F.F. 

Designated Ugly Fat Friend---Usually hangs around extremely Hot girls and DUFF's usually tend to be girls themselves

Bruh do u see dat D.U.F.F. hangin wit Jennifer

D.U.F.F. by WM-Dawg March 27, 2008