The tangy juices that accumulate on the testicles when one has not bathed for a few days or has had vigorous sex and fallen asleep without cleansing the nads.
Jimmy Bobby: What did you make that dang face for?
Jimmy Bobby's sister: Your nuts taste like ball sweat vinegar! Worsh your ass or Ima puttin ma cloths back on!
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.