Ball busting, or ballbusting, is a general colloquial term for any type of cock and ball torture, or genitorture, involving the testicles. Ball busting can consist of actions such as squeezing, tight binding and striking of the testicles, using the hands, feet, or torture aids such as paddles, whips, floggers, humblers and other manmade devices. A ball buster refers to the person who administers these activities.
Ball busting is most commonly a submissive activity delivered by a dominant woman to a submissive male partner. That said, there is also a significant contingent of ball busting enthusiasts in the gay community. Ball busting is also common in pornography, perhaps allowing some people to enjoy it vicariously, rather than in person.