when you are sitting in class and a fart comes along, but you struggle not to release it. The ensuing battle between you and the fart is called a fart battle.
When observing one in the midst of a fart battle they can often be found making funny faces, and are generally enveloped in extreme focus. These battles are extremely dangerous, as the fart could at any moment explode and overwhelm the victim or those those around him/her.
guy 1 - dude today in math I had to fart so bad, it was so hard to keep it in
guy 2- i know what u mean, I have fart battles all the time