'reproachful' originates from Middle English, specifically the word 'reproche,' where 're-' meant 'again' and 'procher' meant 'to approach.'

'reproche' transformed into the modern English word 'reproachful' through the addition of the suffix '-ful' to denote a quality or state.

Initially, it meant 'to approach again with criticism,' but over time it evolved into its current meaning of 'expressing disapproval or disappointment.'