1 definition by Misuta Supakulo

Superhero themed brief style children's underpants (e.g. superman, spiderman, batman, the hulk, etc.) Very popular during the '80s. When used in reference to someone older than approximately 12 implies immature and/or freakish qualities of said person.
Jehannum kicks wedge in the underoos
by Misuta Supakulo March 24, 2004
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