Top Definition
The embarrassing(and sometimes painful) act of your balls hitting against your thigh or leg while walking or running
Me: Dude, I was running my 5k when my balls started hurting

Friend: Sounds like The Flop-Flop
by Brett50Cal July 11, 2012

Free Daily Email

Type your email address below to get our free Urban Word of the Day every morning!

Emails are sent from We'll never spam you.