butt growl 

When your intestines make a churning noise -- similar to your stomach growling -- but you feel it in your butt.

"Dude, did the phone in my back pocket just vibrate, or did my butt growl?"

butt growl by lydiurrr August 21, 2012

Butt growl 

A fart that you successfully keep from escaping but decides to let loose inside and resembles your stomach growling loudly but clearly is not coming from your stomach.

I held that fart in but everyone still heard my butt growl. I was so embarrassed when my butt growled in the middle of class.

Butt growl by Creatrix March 6, 2021