A pre shit fart, is the last bit of gas left over, which takes over the remaining space between your rectum , your poop and the air. It is the worst smelling fart ever, smells like you have shit your sefl, without actually shitting yourself. It is your last and final warning to get your butt to the toilet!
I have been busting ass all the way home, but this last one was a real pre shit fart.

It is the last amount before you are actually praire dogging. A preshit fart is allowing your company to actally smell the authenticity of what your shit would smell like if they were hagging out in the bathroom with you. Mostly, smells like a trucker shit.

Angel just threw a pre-shit fart and then dashed to the bathroom.....almost missing the bowl
by Fartologist December 22, 2013
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