1. Usually when promiscuious male sleeps around either for fun, money, or other perks. This individual doesn't really care who he sleeps with.
2. A male that frequents prostitutes.
Popular in the south. "Truckin' off" is when 2 or more males get together and talk about the additions that they have added or plan on adding to their trucks.
They are extremely excited. It usually starts with a lone truck owner getting a new truck and then another truck owner comes along to "truck off" each other.
Person 1: "Larry and Bob always compare their trucks and talk about what they want to add and modify."
Person 2: "Yea, they love truckin' each other off"
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.