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1.
The ass tambourine is a noun, synonym for balls particularly during the act of sex. Many people are known to describe the act of the balls slapping against a woman's ass or vagina during sex. This makes a very particular slapping sound. The balls serve as the "tambourine," creating a noise during the act of sex.
We played the ass tambourines all night long!
by Darth Rayje June 01, 2010