A term used to describe the urination process that takes place inside a Mcdonalds establishment. Usually after far too much fizzy pop!
Don't eat my burger guys- im off for a McWee.

I can't pull over here Melvin, you should have had a McWee before you left.

Shit...I just McWeed myself...Does anyone have any spare underwear...No?. Shit.

by marc855 July 3, 2006
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