'reward' originates from Old French, specifically the word 'reguard,' where 're-' meant 'again' and 'guard' meant 'to watch or protect.'

'reguard' transformed into the Middle English word 'rewarden,' and eventually became the modern English word 'reward.'

Initially, it meant 'to watch over or protect again,' but over time it evolved into its current meaning of 'to give something in return for good behavior or work.'