You know how Jack Black imitates instrumentals with his voice, like "brig digga dig" and all that stuff?
When someone does that, it is called 'Jack Blacking it'.
Popular among enthusiastic metalheads.
Steve: "DUN DUN DUN- wa nanana, nanana, nanana! DUN DUN DUN- wa nanana, nanana, nanana!"
Dave: "What is it with Steve and 'Raining Blood'?"
Bob: "I'm not sure but he's really Jack Blacking it!"
by VikingGirl March 07, 2010
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A half of the kickass band Tenacious D.
Tribute, My Biznit is the Shiznit, i'm the only gay eskimo
by OgirlO July 22, 2003
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An incredible actor, singer, guitarist and a GOD.

Half of the rock duo TENACIOUS D.

He is also incredibly sexy!
by Ree April 11, 2005
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1. The sexiest fat dude on the planet.
2. The better half of the amazing band Tenacious D.
3. The only celeb who has ever suited both singing and acting perfectly.
by DiamondSerpant April 01, 2007
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The act of masturbating whilst really high so that when you jizz all the blood rushes from your head and you black out. May be hard to achieve.

Also called Knocking Off.
X: "Ben and I tried Jacking Black last night"

Y: "No Way! You guys are crazy! Any success?"

X: "Yep, I totally Jacked Black!! Ben didn't manage to though. It really isn't easy!"
by Jacking it in San Diego April 18, 2015
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