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1.
The kind of smart, know it all, that just wont shut up. Often just pretending to know things, though a real stfugenius wont take so long to shut up.
John is such a stfugenius, he just keeps going on about rocket physics, i dont even care anymore!
by Alex Goold May 30, 2007

Words related to stfugenius

annoying genius smart. stfu