'overflow' originates from Old English, specifically the word 'oferflōwan', where 'ofer-' meant 'over' and 'flōwan' meant 'to flow'.

'oferflōwan' transformed into the Middle English word 'overflowen', and eventually became the modern English word 'overflow'.

Initially, it meant 'to flow over the brim', but over time it evolved into its current meaning of 'exceeding capacity'.