Short for 'Purple Joint', a condition caused by the inability to score when it matters most. Similar to blue-veiners except accompanied by anger, seepage and uncomfortable underwear problems. Purple J's are most common in misogynists, steroid abusers and angry men in fraternity sweaters.
Biff grew rigid looking at the curves defining Trent's tight cut-off jorts and knee-high tube socks. But when the final horn sounded Trent went home and got porked by the winning mascot leaving Biff nursing his bruised ego and a Purple J.