What my dad calls distortion on an electric guitar. My dad's old, and apparently that's what they called distortion in the 60's in North Dakota.
Dad - Hey, does Jason have a fuzz buster on his electric?
Me - A what? No I don't think so.
Dad - Really? He needs one they let you change the sound to all kinds of different stuff.
Me - Oh you mean distortion? yeah he's got that.
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.