Jock was the name of Winston Churchill's cat

a shortening of jockstrap (type of male underwear often used by sportsmen)

Jock Stein - Celtic FC manager (1965-78), a football club in Scotland, and regarded by many as one of the greatest managers the game has ever seen. A gentleman important for much more than just sport, the impact he had socially can never be understated.

Shock jock, a disk jockey known for making off-colour comments on-air

Jockey was originally a diminutive of Jock.

Jock (subculture), an athlete.

Jock of the Bushveld Book by South African author Sir Percy Fitzpatrick, telling of FitzPatrick's travels with his dog Jock during the 1880s

in fiction, Wee Jock was the dog owned by Hamish Macbeth.

Jock (comics), a British comic book artist

The Jocks and the Geordies, a Dandy comic strip

Jocks (film), a 1987 film starring Perry Lang

John of Hazelgreen, ditto

A jock, by most accepted standards of the stereotype (if one is American), is an individual - usually a tall, physically fit, male in his late teens or early twenties - who is well-known for his athletic abilities (This definition is hardly recognised outside of the United States of America and Canada). Jocks are more widely recognized in certain team sports, such as basketball, football, American football, and other physically demanding sports. The term "jock" can be used pejoratively, neutrally, or even complimentarily. The pejorative use refers to an individual whose awareness of his own athletic abilities (or possible lack thereof) gives him the appearance of conceit, real or not to the observer (and in this sense the words "musclehead" and "musclebrain" are sometimes used); and as a result, jocks are often regarded as bullies to their peers, especially those who are not athletically inclined or don't play sports in general. Most famously, the targets of bullying by "jocks" are "nerds" - as popularized by movies such as Revenge of the Nerds - given the idea that the athletically inclined and the intellectually inclined are polar opposites and that the traits each stereotyped group exhibit cannot coexist peacefully.

A pejorative term for a Scottish Soldier (like an English Tommy) and used as a nickname by such units as the British 9th (Scottish) Division, the "Jocks".

Jock the New Engine, a locomotive on the fictional Arlesdale Railway in The Railway Series by Rev. W. Awdry

Jock, Paul Denton's friend and JC Denton's black helicopter pilot in Deus Ex.

Jock series albums by Tommy Boy records is a popular superseries of albums split into subseries like Jock Jams, Jock Rock. However, Slam Jams is part of the superseries abeit omission of "Jock" in the name.

Jock o' the Side, a border ballad