Stands for Fake Ass Friend. Used to call someone out for being fake, sketchy, unreliable, or flaking on something. Not as insulting as a fake ass bitch or a fake ass hoe, but a gender neutral way to describe your frustrations with a friend.
"I can't believe she ditched my birthday party to hang out with her ex. What a faf."
"He posted the group photo where she looked the ugliest. That was such a faf move."
"You're a faf for leaving without me."
"He posted the group photo where she looked the ugliest. That was such a faf move."
"You're a faf for leaving without me."
by definitelynotafaf May 10, 2020
Get the fafmug. Stands for “Funny As Fuck“, used for things that are really funny and deserve more than just a “LOL“. Can also be used as an adjective.
by LelPoel July 1, 2017
Get the FAFmug. "Filthy as Fuck." Expression is used when describing someone whose gross, repulsive, nasty, dirty, rachet; someone you wouldn't touch with a 10 foot pole.
" Ew better get away from him! I heard at the Delta Chi mixer he screwed half the sorority in the coat closet." (On and around your coat.) "That dude is FAF."
by Jennyfrdablock December 10, 2014
Get the FAFmug. 
by FAFlover January 31, 2020
Get the FAFmug. 