When you have loose runing or sport shorts, but no compressing shorts under and one of your testicle pops out the side your shorts while you are streching, doing exercise, etc..
(Tom and Will streching)

Tom: "Will, do some curl ups."

Will: "Ok".(Will get in the postion and starts to do them)

Tom: "Yo, Will"!!

Will: "What"?

Tom: "Dude, your exposing it to some air".

Will: "What"?

Tom: "Man, one of your testicles is hanging out of your shorts".
by TheFoundingFatherL. October 25, 2012
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