look up any word, like blumpkin:
 
1.
yfa
Yoshi fighting association

its the proses when some one eats to many mushrooms and hallucinates since Mario is commonly associated with mushrooms then some one felt it to be the best idea
when some one says "dude are you going to the yfa"
by superdum2 December 04, 2009
 
2.
its a slang word for You Fucking Asshole
Boy:haha you're fat!
Girl: OMG Y.F.A
Boy: its true...
by grrrrrrrrrate July 18, 2009
 
3.
Young Free And Single
Go for it man, she's dtf and you're yfas.
by V10 September 09, 2011