When two partners engage in sexual intercourse and the male performs cunnilingus on the female during her menstrual cycle, he inadvertently collects some of her uterine lining into his mouth. As he finishes the oral sex, the two partners kiss, and the male spits the detritus of blood and menstrual chunks back into her mouth. This is the art of "meatballing," as the chunks represent what looks like a meatball.
meatballs are people that like to drink, like to have fun , have free spirits and they have no rules and regulations. Made popular by snooki and deena.