The word 'usage' entered English in the late Middle English period via Anglo-Norman French, derived from the Old French 'us', a noun form of the verb 'user' (to use). The core Latin root is 'uti', meaning 'to use, employ, or enjoy'. The suffix '-age', a common feature in French-derived nouns, was appended to signify the 'act, manner, or result of using'. Over time, the meaning specialized from the general 'act of using' to also encompass the established, customary manner of employing something, particularly language, reflecting how repeated use solidifies into convention.

Structure: us (use) + age (noun suffix) 'us' from the verb 'use', ultimately from Latin 'uti' (to use). 'age' is a noun-forming suffix from Old French '-age', from Latin '-aticum', indicating a related action, result, or state.