Bartlow is the last name of a person that knows what's what. In some countries, like the USA, they are regarded as royalty and should be. When you get 2 or more together, the more the better, then the possibilities are endless. Most are available for parties and bar mitzvahs upon request.
A bertlow is anyone who lives in the bad part of town, has had 50 different jobs in 3 months, etc. Also known as a loser, scrub, etc. Comes from Wickenburg, AZ, where a man named "Bertlow" was such a loser that the town's youth started calling all losers "bertlow".
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.