jockstrap

The word 'jockstrap' is a compound formed in American English in the late 19th century. Its first element, 'jock', is a slang abbreviation of 'jockstrap', which itself is derived from the earlier slang term 'jock' for 'penis', a Scots variant of the name 'Jock' (a common nickname for John). The second element, 'strap', comes from Old English via Latin, meaning a narrow band of flexible material. Thus, the term's literal composition evolved from a descriptive term for a supporting band for the male genitals to its modern, specialized meaning as protective athletic gear.

Structure: jock (athlete) + strap (band) - jock: Origin: Shortened from 'jockstrap' itself, later reanalyzed as slang for 'athlete'. Functional role: Specifies the user or purpose. - strap: Origin: Middle English, from Old English stropp, from Latin stroppus 'thong, band'. Functional role: Denotes the object's form (a band or support).