'two-footed' originates from Old English elements: 'twā' (meaning 'two') and 'fōt' (meaning 'foot'), combined with the adjective-forming suffix '-ed'.

'two-footed' changed from Old English compound forms such as 'twāfōted' (or analyzed as 'twā' + 'fōt' + '-ed') and eventually became the modern English compound 'two-footed'.

Initially it meant 'having two feet' (a literal description). Over time the literal sense has largely remained, though a secondary use developed to describe length (i.e., 'measuring two feet').