What does Bungthump mean?

Bungthump meaning in Urban Dictionary

as a result of misinterpretation of a bung as a "butthole," a bungthump is slang for whenever two or more men and women, whether of the same sex or not, which can be significantly more than acquaintances lay on the ground in a circle on knees and elbows, each facing each other's rears in counter-clockwise course, and thump the rectum of the individual in front of all of them with the center hand to their right hand. This is generally practiced at frat events and backstage permanently fortune at metal concerts.