A feeble, weak specimen of a human being who when he needs to urinate must adopt a "sit down position" due to him having a maggot sized penis hence the saying sit down pisser!
Mark kicked open the toilet cubicle door to find Elliot having a "Sit down piss".

His penis was so tiny that he couldnt hold it to urinate, he had to "sit down for a piss".
by A.non May 20, 2006
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