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The act in which an erect penis detatches itself and forms arms, teeth, feet, and a tail. It then tends to rampage across cities endlessly. The only cure, find a boner-shrinking image; such as Paris Hilton
Tom: Oh my god, is that set of boobs glowing?! I think im getting a boner!!! OH NO! WATCH OUT!

Jerry: What is THAT?

Tom: Its a bonersaurus! Run, Quick! Find a poster of Paris!!

Oh thank god we stopped the brute.
by Alfonzogarbanzo June 17, 2010
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