An extremely loud that makes your butthole explode and rumble, and when it comes out it sounds like you accidentally stepped on a duck and it screamed. Usually happens when you hold a fart until you can't hold it anymore.
Bruno: *hardly and loudly farts*
Reese: "Yo Bruno, what did ya just step on a duck?!"
Bruno: "Yeah, and it feels like my ass ripped in half."
Reese: "Pull yourself together, dude."