Top Definition
Jock Strap, Athletic Supporter. Boys/Men wear these things in gym class and other athletic activities.
"I gotta put on my sack jacket so my balls aren't thrown around like a rag doll."
by laurynko November 13, 2011

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.