The cleavage created by a fat man's man boobs with folds of fat resembling a vagina. The name is derived from the fact that the man boobs require a bra.
Look at that overweight puerto rican man, he is always sweating and his tits make a bragina.
A cross between the name "Brian" and "Vagina" used to piss off, irritate, or simply make fun of those named Brian. Typically used to emphasize vagina-likeness to a man. Variations (John to Vajohna) can also be implemented.
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.