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An acronym meaning, "My life is so fun!" To be said when one is having so much fun that he/she is content with life, causing him/her to resound in a hearty "MLISF".

An antonym of MLISH, or m-lish.
Omg, guys, I'm going on vacation to Disney! MLISF!
by dudebroyeah July 12, 2011