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The tool used to cut in half a log of human waste so impossibly long that it won't fit down the toilet hole. Usually a butcher knife.
Yeah, i took such a huge dump my dad had to cut it in half with a shat bisector before he could use the toilet.

Hey, go wash off the butcher knife, it's in the kitchen sink, i had to use it as a shat bisector
by Stella Teets July 29, 2006
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