Generic term for beer. Originates from The Simpsons cartoon series, where Duff is the brand of beer characters drink.
by Karl Steiger January 31, 2004

by sophuct72 February 5, 2010

Duff is an acronym meaning Dumb Ugly Fat Friend or Designated Ugly Fat Friend.
Generally a cockblocker and a bitch, have a desperate friend take her down.
Generally a cockblocker and a bitch, have a desperate friend take her down.
Friend 1: Dude I want to hook up with that girl, but her duff is in my way.
Friend 2: It may be Amber but i'll take the duff down.
Friend 2: It may be Amber but i'll take the duff down.
by Jap Anus Relations July 29, 2009

by mobojobo February 2, 2015

a duff is another definition of a noob; a term used when sombody makes a stupid mistake or does something stupid.
Alex: oh my god my ball hairs itch like hell, man.
Morgan: wait, you have hair on your balls.
Alex: wow, your a fucking duff.
Morgan: wait, you have hair on your balls.
Alex: wow, your a fucking duff.
by DJCVans June 30, 2006

designated ugly friend.- the girl no guy wants to have.
This girl will usually get ignored when out with her hot friend and may be so ugly the wingman won't even touch her- then the cockblocking comes in.
The ugly friend may suffer from some form of facial deformity such as an outrageously large nose which prevents them from anyone finding them physically attractive.
They usually end up nowhere in life due to their unnatractive looks and may become a stalker so watch out.
This girl will usually get ignored when out with her hot friend and may be so ugly the wingman won't even touch her- then the cockblocking comes in.
The ugly friend may suffer from some form of facial deformity such as an outrageously large nose which prevents them from anyone finding them physically attractive.
They usually end up nowhere in life due to their unnatractive looks and may become a stalker so watch out.
by jdjdjd5665 December 16, 2008
