The bodily sensation when you are forced to turn your fart "inward", back into the body, instead of letting out into the atmosphere. This usually occurs in social situations, like a date, or an important meeting or interview.
"Man, I was in Johnsons office this afternoon, and after eating all those eggs this morning I was riddled with poopbusters"
It is said of the situation where a person has the bad luck to make contact with his testicles against an undefined surface or object, intentioned or not.
Given the nature of the word, it is more appropriate to design cases where the interaction is made with a moving object, for example, a ball.
Although it is extremely painful for the victim, it tends to be considerably funny to people who witness it.
Today in the baseball game the pitcher took a nutshot; the baseball hit him in the nuts.
Man, I just watched the funniest nutshot video ever.