This word is a mere slang Arabic, which roughly means Teddy Bear.
It can be said to someone you have feelings for: a friend, a child, a lover and any of your family members except for mom and dad of course.
Teddy Bears can be hold and kept close to kids most of the time, so when calling the one you love my dabdoub, it expresses the feeling that you want to hold them, for instance!.
Heyy, you're my dabdoub . Please don't be sad, I'll see you soon.
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.