Acronym meaning designated ugly fat friend. This is the disgusting ugly fat friend that tags along with the hot chicks. Said hot chicks allow this as it makes them look less shallow and more attractive.
Ian: I've been tryin' to get Jenna alone for weeks now, but Bertha's always around.

Shawn: Ew, dude, Bertha's a total DUFF.

Ian: You think you could hold her attention while I talk to Jenna?

Shawn: That depends on how much you're willing to pay me.
by xdanielx August 07, 2008
1. Designated Ugly/Fat Friend
a friend that hot girls have to make themselves feel hotter
2. someones butt
1. Every hot girl I see seems to have a duff
2. Get off yer duff and do some work!
by Poopie pants 2 October 25, 2007
Designated Ugly Fat Friend not to be confused with the fuckin amazing duff mckagan. This person often makes you feel better about yourself when your around them...they make you look good
my friend lindsay is a duff when we go out
by slashsbabe_420 May 25, 2007
Most commonly known as the girl that your hott date has to take along with her to the x dance. Your date won't go without her so she has to come along. The whole time she gets in the way of you two. Duff stands for designated ugly fat friend. Very terrifying moments have been caused by this race of people.
Bess: "Hey, we should go to Mikes this weekend."
Kailey: "Yeah, thats a great idea. We should take someone else, just in case things get a little too weird."
Bess: "Lets take Sarah. Shes always a good conversation peice."
Sarah= DUFF= Ugly, fat, facial hair, and zits
Everything every "man" wants
by Stanely Jr. October 06, 2005
When a woman has been fertilised by a man. I.e she is pregnant
She is up the duff
by Johan Forssander March 03, 2004
Free Daily Email

Type your email address below to get our free Urban Word of the Day every morning!

Emails are sent from We'll never spam you.