Noun - To say or do something to unknowingly make an utter fool of oneself.

The process of pulling a kjo is called "to be kjo'd"
E.g.

Kanu: Dude, I'm a maths champion!
Shaggy: Prove it!
Kanu: 12.5 x 2 = 35
Shaggy: What a kjo you are
PK: Haha, you've just been KJo'd!
by arjwiz April 5, 2012
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