An acronym for, laughing my fucking ass off at you, big fat monkey. 1. Used as an insult or 2. just joking around.
1. prson1: I HATE U IM GLAD U TRIPPED AT LUNCH LMFAOUBFM!!!!

2. prson1: LOL! Did you see that person trip at lunch! I was soo like LMFAOUBFM!!!! xD
by bberger May 30, 2011
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