The word you yell when you are about to let loose a serious case of projectile diarrhea. Usually into the toilet or into the back of the toilet bowl (sometimes on the seat or completely out of the toilet as a whole).
Sometimes said like this: SHOT!... Guun!!!
(a quick "SHOT!" followed by a 1.5 second pause, then "Guun!!!")
Two Guys in a public restroom:
Pooper1: Good afternoon.
Pooper2: SHOTGUN!!! (In Tandem with projectile Diarrhea.)
Pooper1: The fuck? LOL!
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