1. A class of giant fighting robots in the Anime series Big O. Several robots can be seen throughout the series, the most popular ones being Big O, and it's archenemy, Big Duo.

2. A massive, steaming pile of shit.
1:
Oh my God! It's Megadeuce! He's coming to save the day!

2:
Man, I wouldn't go in there, I just dropped a MEGADEUCE, and it's peeling the paint off the walls as we speak.
by Krunk! December 10, 2003
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