southerly

the word 'southerly' is built upon the old english root 'sūþ', which denotes the cardinal direction. the addition of the '-er' suffix creates the comparative form 'souther', historically used to mean "more southern" or "from the south." finally, the adverbial '-ly' suffix is appended, a productive suffix from old english '-lice', which converts adjectives into adverbs. thus, the literal construction "in a southern manner" evolved to specifically describe both direction toward the south and, importantly for meteorology, winds originating from the south. this layered morphology illustrates how english combines native elements to create precise descriptive terms for direction and wind.

Structure: south + er + ly - south: from old english 'sūþ', meaning "south, southern region" - er: a suffix forming comparative adjectives or agent nouns; here, it forms the adjective 'souther' (more southern) - ly: an adverbial suffix meaning "in a manner or direction of"