The compound adjective 'warm-season' is a modern English formation that logically combines two native concepts. The first element, 'warm', descends from the Proto-Germanic warmaz, a fundamental term for a pleasant, moderate heat. The second element, 'season', has a more complex journey, originating from the Latin satio meaning 'sowing', which evolved in Vulgar Latin to denote a 'sowing time' and was borrowed into Old French. In English, it broadened to mean any distinct period of the year. When combined, the term creates a precise horticultural and agricultural classification, directly linking the literal quality of temperature ('warm') to a specific temporal phase ('season') to describe plants adapted to that condition.

Structure: warm (sense) + season (sense) - warm: From Old English wearm, meaning having a moderate degree of heat. Its functional role is to modify the noun 'season', specifying the type. - season: From Old French seson, ultimately from Latin sationem (sowing), later generalized to a period of time. Its functional role is the core noun being modified.