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a person who has amazing yet insane moments during a time that is supposed to be focused or serious.

-this person usually has a buddy or two who create the mayhem or do idiotic things that make it all just fantastic
Aldo: Hey did you see Quinn and Anna messing up the board in geometry today?

Hannah: Of course i did, who do you think told them to write queef up there?

Aldo: wow you guys are qacks...
by LittleAnnaKins January 26, 2010
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