'arched-footed' originates from Modern English, specifically the combination of 'arched' (past participle of 'arch') and 'footed' (from 'foot'), where 'arch' ultimately comes from Latin 'arcus' meaning 'bow, arch' and 'foot' comes from Old English 'fōt' meaning 'foot'.

'arched' developed from the adjective and past participle of 'arch' formed in Middle and Early Modern English; 'footed' derives from Old English 'fōt' with the suffix '-ed' to indicate having a foot or feet, and the compound 'arched-footed' follows the modern English pattern of adjective compounds combining descriptive past participles and '-footed' constructions.

Initially, the elements referred separately to a 'bow/curve' ('arch') and 'foot'; over time the compound came to describe the particular physical characteristic of having a pronounced arch in the foot rather than separate meanings.