This is the coolest of cool, the sweetest of sweet. Offen used in gaming situations where a combo or other impressive move was used on an opponent.
Sometimes used in the real world to describe somting "sweet" or "wicked".
"Dude, did you see my rocket+nail+rail gun combo frag, it was totally ninja!"

"Hard|OCP and Slashdot are both totally ninja!"
by Minn0W June 1, 2006
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