end-of-season

The term is a modern compound formed entirely within English. It logically combines the noun "end," from Old English ende (meaning limit, boundary, or conclusion), the preposition "of," from Old English of, and the noun "season," from Old French seson, seison, ultimately from Latin sationem (meaning a sowing, later a time for sowing, and then a period of time). The phrase "end of season" originated as a simple descriptive phrase. Through frequent use in commercial and sporting contexts, it has become a fixed lexical unit, a hyphenated compound adjective used to describe events, sales, or performances that mark the conclusion of a defined cyclical period.

This is a compound adjective formed from a prepositional phrase ("end of season"). It is not productively segmentable into classical morphemes for etymological analysis as it is a modern English syntactic construction lexicalized into a fixed modifier.