'fleet-footed' is a compound word formed from 'fleet' (meaning 'swift') and 'footed' (meaning 'having feet'). 'Fleet' comes from Old English 'fleotan' meaning 'to float, to move swiftly'.

'fleet-footed' was formed in English by combining 'fleet' and 'footed' to describe someone or something that moves quickly on their feet.

Initially, it described someone who was literally fast on their feet, and it still retains this meaning today, sometimes used figuratively for anything fast-moving.