Basically you're 'laughing out loud', but then you remember you dropped your keys or the joke was actually a proposition.
Laugh
Out
Lou-FUCK!

Person A says:
i love you. i want your babies.

Person B says:
lolF
by iwantyourbabies February 28, 2009
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"LOLF that was soo funny"
by Helen (Pinky) February 9, 2008
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This is an expression used in place of 'lol' because saying lol is tacky. It stands for Laugh Out Loud Floor's Hairy Arse Rabbits Riding In Scooters.
Oh my god, he has his shorts on backwards. Lolf harris.
by Imminent fate August 20, 2008
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