Originally means "work on Marvelous Attack", originally meant for the PC game Stepmania. Outside of the game, however, you can use it as a comeback similar to that of no u and your mom.
For use in Stepmania:

Moogy: ZOMG I GOT LIEK 200 PERFS ON STRANGEPROGRAM!11!1!!1!!one!1!! o btw u have aids
DigitalCyber: work on MA

For use in real-life situations:

emo kid: i hate life
non-emo kid: work on MA

someone who loves fat chicks: i just boned a fat chick
someone who doesnt: work on MA

black person: hi
white person: work on MA
by #1 Messi Fan September 10, 2006
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