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3.
Fine, Understood, My Friend
Guy1: I no you are, but I am not.
GuY2: FUMF
by Digmor July 05, 2013
 
1.
short for f#!k you mother f*^$&r
'Man you suck'
'fumf, ill beat your ass'
by Angel,king of the mountain November 24, 2004
 
2.
fumf - fucked up motherfucker

Usually used if we are describing someone crazy or out of their mind.
John: Hey man! Did you see James?! He was driving 150 MPH on this short, narrow street!

Jerry: Yeah. He really is a fumf.
by Khorin April 21, 2008