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1.
The acronym for Food Is For Fatties. Often shouted by girls who dont eat and are obsessed with gaining weight.
Ashley asked Gina "Where are we going for lunch?"
Gina shouts "FIFF!! We're on a strict water and exlax diet!"
by VaGyna August 18, 2008
 
2.
Finally It's Fucking Friday!
FIFF!

I know what you mean.
by petre dish January 24, 2014