The shit-fart separator (AKA shitfart separator) is the muscle inside your colon, just above your bunghole, that is responsible for separating shits from farts. Usually a dormant muscle, the shit-fart separator is often only noticed if it's repeatedly squeezing and churning when one has diarrhea. The work of a healthy shit-fart separator usually results in dry farts.

I had bad diarrhea, and my shit-fart separator was in overdrive.

My shit-fart separator failed me and I accidentally sharted a little in my underwear.
by Flambo Blumpkin February 14, 2008
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AKA SFS The shit fart separator is the divice inside your ass that separates your shit from your farts. Without this divice everything turns into a shart.
Dude are you trying to fart.
No man im testing my shit fart separator.
by RedlegArtillerymen August 21, 2008
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