The compound adjective 'well-turned' is a product of the English language's capacity for descriptive synthesis. Its core logic originates from the craft of woodworking or metalworking, where the verb 'turn'—derived from the Latin tornare, meaning to shape on a lathe—literally meant to give a rounded, finished form to an object. By the 16th century, this literal sense was metaphorically extended to the crafting of language, with 'well' serving as an intensifier of quality. Thus, a 'well-turned' phrase is one that has been skillfully shaped and polished for elegance, while a 'well-turned' ankle is one perceived as having a gracefully formed contour.

Structure: well (good) + turn (shape/form) + ed (adjective suffix) - well: From Old English wel, meaning "in a good way, properly, satisfactorily." It functions as an intensifying adverb modifying the verb root. - turn: From Old English turnian and Old French torner, from Latin tornare ("to turn on a lathe, round off"). It functions as the verbal root meaning to shape or form. - ed: A common English suffix forming past participles and adjectives from verbs, indicating a state or condition.