'rebate' originates from Old French, specifically the word 'rebattre' (also seen as 'rabattre'), where the prefix 're-' meant 'again' and 'battre' meant 'to beat'.

'rebattre' (Old French) developed into Middle French forms like 'rabatre'/'rabattre' and entered English in late Middle English/early Modern English as forms such as 'rebaten' or 'rebate', eventually becoming the modern English 'rebate'.

Initially it meant 'to beat back' or 'to reduce (by striking down)'; over time the sense shifted to 'a reduction' or 'a return of part of a payment' and to the verb meaning 'to give such a reduction or return'.