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A term to define an short girl with a large ass, pig nose and short, stubby arms. She runs like a raptor, and when she stops moving the smell of ass moves in for it's silent but deadly kill. This girl will also have a large, large, gianormous vagina. It will be so large/loose that when you stick 3 fingers to a fist insider her vagina and she will not even know it is there.
Boy: "OMG, Look at that girl with the big ass, short stubby arms, and the pig nose that runs like a raptor."

Girl: "That's a Moni-rex-asaurus"

Boy: "Do you smell ass?"
by Tokin' Gay Dude May 28, 2010
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