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When someone is acting so outstandingly white or retarded that they are now acting like they have a case of autism or like a tism bear.

*not to be confused with people with autism, mostly used in context for describing wiggers.
Person A: Yi Yi Yi Yi im a hood rat and im so black yi yi yi!!!

Person B (looking from a distance): What a tism bear
by johnnyq77 June 21, 2011
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