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1. LMFO
Laughing my Face off.
That shit was so funny I was LMFO!!!
2. LMFO
Her dress made me LMFO.
3. LMFO
Laughing my face off.
Bob-So I was like "hey baby, can I buy you a drink?" And she was like "only if I can throw it in your face!"

Me-LMFO
4. Lmfo
New Net slang for people who do not enjoy cursing. Meaning Laughing My Face/Foot (whichever you like) Off. I suggest Face.
Lmfo.. Layluhh that is SO funny.
5. LMFO
Laughing my Face off.
That shit was so funny I was LMFO!!!
6. LMFO
Chat lingo for Laugh My Fuck Off. Let's chatters use there imagination when chatting, instead of having a direct meaning like LMFAO, for each person a fuck could be something else.
e.x:

chatter1- did see what that guy did in the pizza place?
chatter2- ya! i was like LMFO
7. lmfo
Let me Find Out
Lmfo "Aventura" Says dat all the time