A common man.
A Scotsman.
The penis.
An athletic supporter worn by men to support the genitals especially during sports, a jockstrap.
A young male athlete (through college age).
An enthusiastic athlete or sports fan, especially one with few other interests. A slow-witted person of large size and great physical strength. A pretty boy that shows off in sport.
A disc jockey.
(in combination) A specialist computer programmer.
a compiler jock; a systems jock