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1.
n. The act of forcing the scrotum and testicles into another person's mouth, creating a gargling noise. Much like a teabag, but more violent.
"No! Not the rock tumbler! Noooooo! (Gargle)."
by Whitby July 21, 2003
29 20
 
2.
When two or more people get into a garbage bag, close it, and have sex while tumbling down flights of stairs.

Very common in Eastern Asia.
Soon-Kwok Woo and Aika Sekihotai set the world record for "Rock Tumbling" down 65 flights of stairs without stoping. All that was left of them inside the bag was a gooey, oriental mush.
by JJ January 19, 2004
7 12