bull jacker 

an individual who collects bull semen for subsequent insemination of cows

Bob was careful to always wear safety gloves, because he knew that his hands needed to be in perfect shape for his first bull jacker gig.

bull jacker by veebervitzer December 13, 2013

balljacker 

1.a lazy person.
2.a person with so much time on their hands as to be compared to fiddling with ones own testicles.
3.germanthe person,not the nationality

"german doesn't do anything. He's such a balljacker"

balljacker by Jay Bain January 12, 2008