As you have read, it means Laughing My Ass Off, but what has NOT been explained is
the origin. Laughing is
supposed to be the best medicine, but it is also the best exercise. Well, behind sex and walking. Anyways, if you laugh, you lose weight, hence laughing your ass off.
Sara- I LMAO-ed so much last night I think I lost weight!
Thanks so much sweetie!
Joe- Ya, I was hoping
you would.
Sara- *GASP* *SLAP* WE ARE THROUGH!
Joe- I was jk!!!!!! LMAO
Sara-
NOT FUNNY JOE!
Joe- *snickers*
Sara- I hate you.
Joe- Wanna do it? You'll lose those last 5 pounds...
Sara- .... Fine. But JUST this once!