The word 'unseasonably' is built upon the core concept of a 'season,' which traces back to the Latin sationem, meaning 'a sowing.' This agricultural root evolved in Old French to denote a suitable time, eventually specializing in English to mean one of the four climatic periods of the year. The prefix 'un-' negates the typical quality associated with that time, and the suffix '-ably' transforms the adjective 'unseasonable' into an adverb, describing an action performed in a manner contrary to seasonal norms. Thus, the term logically progresses from the concrete act of sowing at a proper time to the abstract modern sense of deviation from expected weather patterns.

Structure: un (not) + season (period of the year) + ably (in a manner of) - un: A prefix of Germanic origin (Old English, Old High German, Old Norse) meaning "not," used to form negatives. - season: From Old French seson, seison, ultimately from Latin sationem (sowing), later sation- (time of sowing, season). Its role is the core noun root. - ably: A suffix forming adverbs from adjectives, from Latin -abilis (able to be) via Old French -able, combined with the adverbial suffix -ly (from Old English -lice).