BMF4U 

Literal translation is "Big Midddle Finger for You". Commonly used toward someone who has done something incorrectly, and you are telling them that you don't care/can't do anything about it.

You scratched the hell out of your CD and it doesn't work anymore? Well, BMF4U.

BMF4U by Ralakan April 15, 2003

BMFU 

Beat Mother Fuckers Up

The wrestling mat is where you proclaim to BMFU.

BMFU by Wrestle or Die September 19, 2018

BMFU 

By me fuck you

Homie: man you suck at this game
You: bmfu

BMFU by ᠻ𝙞𝙚𝙣𝙙 January 5, 2021