1 definition by AgentSakur9

Top Definition

a name given to a person of whom knows you but you can't recall his name to save your life. portmanteau of What's Up + Dude.

SupDude: Hey Hey Hey Mike!

Mike:Hey........ SupDude!

Later...

Amanda:Who was that?

Mike: SupDude.

by AgentSakur9 March 01, 2010