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An internet slang term meaning laughing but super furious.
I forgot my homework at home, lbsf.
I tried a lame pick up line on the girl I like and it didn't work, lbsf.
by SomeRandomLettersAreASDKLJFLKD December 22, 2012
2 1
Laughing but so fuckkin serious...
me: stop, don't tickle me

boyfriend: come on bay, i wanna see you smile.

Me: smilin these nuts, don't touch me

Boyfriend: come on

Me: lbsfs GONE bay damn
by tokiio July 22, 2010
3 10