A fat man who still lives in his mom's basement well into adulthood. Basically another word for Momma's Boy.
Guy 1: Guys I'm 30 and I live in my mom's basement, oh and I weigh 300 pounds!
Guy 2: Ha ha, you're a Carnbarn!
Guy 1's Mom: Carnbarn come here! I baked you some cookies!
by ThayTah March 12, 2009
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