Definitions by Pete-ay and Jimmy smooth.

The fly 

separating your nads with your boxers, creating an effect that, well, looks like a fly. Then you chase any unsuspecting friends/family/colleagues/children with. May result in jailtime.

"Hey Jim, look here"
"Whats that pete?"
"THE FLY!!!!!"
"AAAARRRRRGGGGHHH! wtf lol"

The fly by Pete-ay and Jimmy smooth. February 25, 2009