Young Brunette Girl Undresses Her White Chemise And French High-cut Briefs At Home

In the UK, briefs were first sold in 1938. Soon, shops were selling 3,000 briefs per week. They were so popular that in 1948, every member of the British Olympic team was given a free pair of briefs.
In Britain, the term "jockeys" has not caught on and briefs are often referred to as "Y-fronts". The term derives from the inverted Y-shape formed by the seams at the front of the underpants which purports to allow easy access to the penis for urination. The colloquialism is used even when the fly opening may differ in style, and not actually form the shape of the inverted letter "Y" fly on Cooper Jockey brand briefs.
In Australia, briefs are referred to as "jocks", but should not be confused with jockstraps (more specifically used by athletes) which expose the buttocks. Australians generally use the word briefs to refer to the bikini-style underwear for men, which do not have the Y-front opening.
In the United States, a slang term for briefs is "tighty-whiteys" (with various spellings and inversions: "tidy-whities", "whitie-tighties", etc.). The exact origin of the term is unknown, but it has often been used as an epithet.