short for My Ass Just Fell Off.
it means something is so funny that you laughed your ass right off.
can be used instead of LOL, LMAO, ROFL, ect.
i totally created it
bobby: theres a party today
cindy: where?
bobby: in my pants
cindy: MAJFO!
by caitlynrocksurlife October 7, 2006
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