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1.
The fat, ugly girl who hangs out with a group of very attractive women. The big fat friend is a notorious cock block and will do whatevr she can to prevent you from sleeping with her friends. Her biggest weakness is the non-discriminating wingman who will sleep with anyone.
I was macking on this girl, but her big fat friend wouldn't leave us alone.
by Mufasa25 October 01, 2008
51 6
 
2.
Usually a female friend of your girlfriend. You HAVE to get on with her for the sake of your relationship but she doesn't make it easy! She'll make sarcy comments, Make fun of you and demand to be everywhere that you and your girlfriend go.

Listen to "Big Fat Friend by Stephen Lynch" for more info :P
Guy 1: Oh hey did you end up getting with Rachel last night?

Guy 2: Nah her Big Fat Friend was there the whole night, Wouldn't fucking leave man

Guy 1: That sucks, just bring her a picnic basket next time!
by Killleera7x December 23, 2008
14 15