'refill' originates from the English combination of the prefix 're-' (from Latin 're-' meaning 'again') and the verb 'fill' (from Old English 'fyllan').

'refill' was formed by combining the prefix 're-' with Middle English 'fillen' (from Old English 'fyllan'); over time this produced the modern English word 'refill'.

Initially, 'fill' (Old English 'fyllan') meant 'to make full'; the formed word 'refill' came to mean specifically 'to make full again' and that sense has remained.