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The awesome of having a fu manchu moustache
Ang: What is that hideousness?
Me: It's the fuckin fu!
by marty and chris May 26, 2009
John Cena's finisher move (came before the STFU).
He came up with this name when he was in a fewd with Brock Lesnar, whose finisher move was the F-5.
Also an abbreviation of 'F*** You.'
"Yo, Brock, your finsher's the F-5 - well, mine's the F-U!!

Person 1: (gets nudged by bypasser) Aww, F-U!!
Bypasser: Dammit, just say the word man!
by Greg A Woodin August 04, 2007