When someone farts, and someone else nearby (in the same room) tries to take credit for that fart.
Hey, I just cranked out a loud wet fart and that guy over there tried to fartjack it and take credit for himself. Damn fartjacker!
When someone fails to fart after repeated attempts and become very frustrated and upset about it.
The other day, I really wanted to fart. I tried so many times, I squeezed, grunted, and even screamed, but nothing would come out! I was so fartbroken.