When a penis and testicles ends up flapping or moving around becoming visible to bystanders. Often happens when a person jumps or moves erratically. This can happen when a person is naked or clothed.
There was thromping in that man's pants while he was dancing.
by Hugh Diggler November 22, 2010
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The middle ground between "thrash" and "pump." Euphemism for hard core sex.
by Chicklet July 12, 2004
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