'pain-conscious' originates from Modern English, specifically formed by combining the noun 'pain' and the adjective 'conscious' (both existing English words).

'pain' descends from Old English 'pīn' (from Latin 'poena' via Old French), where 'poena' originally meant 'punishment' and shifted to 'suffering'/'physical pain'. 'conscious' comes from Latin 'conscius'/'conscire' (to know with), via Middle French and Middle English into Modern English 'conscious'. These elements were later combined in Modern English to form the compound adjective 'pain-conscious'.

Initially, 'pain' had associations with 'punishment' in its earliest borrowings, but over time the sense moved to 'physical suffering'; 'conscious' originally meant 'knowing with' (aware). Combined in Modern English, they yield 'aware of pain' or 'sensitive to pain'.