Athletes penis 

Irritation and itching to the crotch after excessive sweating. Also known in some circles as "trench dick"

"Hey bro you wanna go do sit ups in the hallway?" "Sorry bro I got a mad case of athletes penis. Yolo."

Athletes penis by jockstrap on June 25, 2014

Athlete’s Penis 

Term used to describe the condition of a persons manhood after it has been subjected to a long night of sexual intercourse (usually without a condom), or over-enthusiastic masturbation. Normally red, throbbing and sore to the touch.

Oli: Did you have a good time with that slut last night then?
Mark: Yeah but my dick is so sore today.
Oli: Chlamydia?
Mark: Nah mate probs just a severe case of athlete’s penis.

Athlete’s Penis by Neddie Walker November 14, 2011

Athlete's Penis 

A case where, due to excessive exercise, a man's penis is smaller than normal. Unlike athlete's foot, athlete's penis is not caused by fungus infections. It happens because all of the blood that would usually keep a man's penis his normal size is being used in his muscles. This is not contagious, but very demoralizing to said man.

Person A: "Ah man, it sucks Harrison got pantsed in from of Allie!"
Person B: "Yeah that was the worst case of Athlete's Penis I've ever seen! I don't know if he'll ever be able to live it down..."

Athlete's Penis by Future Mind-Controling Robots July 9, 2010