Reverse Diarrhea 

When you go take a dumb/crap/shit and your shit hits the water hard enough so the water ends up going up and the water touches your ass.

Bob: Well my day is ruined!
Jack: Why?
Bob: I had reverse diarrhea
Jack: wtf is that?
Bob: Its when you go shit and your shit lands in the water really hard and the water splashes against your ass.

Reverse Diarrhea by Junsquared December 31, 2011

Reverse Diarrhea 

Taking a shit and then painfully shoving it back up your ass.

I went back to my ex and now I have a bout of reverse diarrhea. Lesson learned!

Reverse Diarrhea by John Gunner February 18, 2017

reverse diarrhea 

a health condition where feces, especially diarrhea comes out of the mouth

Yesterday, I had reverse diarrhea. It sure tasted gross.

reverse diarrhea by Billiam Beaver June 14, 2018