a knife made of medal, glass, rock, ect. normaly by prisoners in prison.
prisoner1: yo did you hear about bill.

prisoner2: ya bob killed him with a prison knife.

prisoner1: sad.

prisoner2: ya.

prisoner1: he had kids.

prisoner2: didn't you know that's how he got here he killed them.

prisoner1: oh no I droped my soap.
by josh 1 January 19, 2012
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