belly fart 

when you hold a fart in for so long it goes up into yur belly and makes a noise

vikki was at a wedding the other day and everything was quiet, she needed to fart but she held it in and did a belly fart

belly fart by ella-jade May 2, 2007

Bell Fart 

Sometimes during masturbation, a pocket of air becomes trapped under the foreskin. Upon pulling back the foreskin the air is released creating a sound similar to a fart.

Man: "Pfft."
Woman: Did you just fart honey?
Man: No, that was a bell fart. You wouldn't have sex with me tonight, so I'm relieving myself.

Bell Fart by Kelfaur January 31, 2014

Bully-fart bag 

a bag in which a coal sample is put in, but instead of having coal in there you take it and put it up to your ass and fart. then you take it and put it in someone's face and ask them if they know the bully-fart man.

Man alive! that was the sickest bully-fart bag i ever smelt!

Bully-fart bag by Broagan Lee Goertz June 27, 2006