Kneeballing is when the knee is used to inflict pain on a mans testicles whether for sexual fun or self defense, derived from tamakeri/ballbusting. Practiced by many as an introduction th ballbusting.
by Drew1977 April 25, 2016

the place under your knee that when it gets hit it feels like you got kicked in the balls. Except on your knee.
by chaddaddy69 October 16, 2008
