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a move personally made up from the batwing, a cruel joke, mostly done by other teenagers, where you take your scrotum, spread half of your sac out with your hand, and cup the other nut in your hand like a brain. takes a while to get right, but when accomplished, is better than the batwing
I flashed robert with the bat brain, and he threw up!

Adam scared a kid with the bat brain.

by bodhi williams March 25, 2008
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A Batman fan who always has Batman on the brain.
Ever since Tim saw his first Batman movie, he's been a total batbrain.
Mr.Person A:Yesterday I saw some nerd running around in a Batman suit.
Mr.Person B:What a batbrain.
by Wilddwarf June 27, 2009
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