Support briefs

A jockstrap (also known as a jock, jock strap, strap, supporter, or athletic supporter) is an undergarment for supporting the male genitalia during cycling, sports or other vigorous physical activity and now commonly worn as everyday underwear. A jockstrap consists of a waistband (usually elastic) with a support pouch for the genitalia and two elastic straps affixed to the base of the pouch and to the left and right sides of the waistband at the hip. The pouch, in some varieties, may be fitted with a pocket to hold an abdominal guard (impact resistant cup, box) to protect the testicles and the penis from injury.

Jockstraps for athletic purposes are most commonly worn in North America.

More recently, 'fashion jockstraps' have become increasingly popular as regular underwear worn by men as an alternative to other styles. Fashion jockstraps follow the design of the sports models but are worn as everyday underwear. Fashion jockstraps appear in a variety of colours and fabrics.

The word jockstrap has purportedly been in use at least since 1888, a likely contraction of "jockey strap", as the garment was first designed for bicycle-riding messengers and deliverymen, or 'bike jockeys'. The Bike Jockey Strap was the first jockstrap manufactured in America in 1874.

Jockey meaning 'rider', primarily a race horse rider, has been in use since 1670. Jockey itself is the diminutive form of the Scots nickname Jock (for John) as Jackie is for the English nickname Jack. The nicknames Jack and Jackie, Jock and Jockey have been used generically for 'man, fellow, boy, common man'. From the period c.1650-c.1850, 'jock' was used as slang for penis.

The more recent American slang term 'jock', meaning an athlete, is traced to 1959 and is itself derived from 'jockstrap'.

The jockstrap was invented in 1874 by C. F. Bennett of a Chicago sporting goods company, Sharp & Smith, to provide comfort and support for bicycle jockeys working the cobblestone streets of Boston. In 1897 Bennett's newly formed Bike Web Company patented and began mass-producing the Bike Jockey Strap. The Bike Web Company later became known as the Bike Company. Bike was, until 2016, a leading produced of jockstraps. In that year, the company and its trademarks were purchased by Russell Athletic.

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Wikipedia