1. Money that is paid back; for example, because someone has overpaid a tax or is entitled to a refund: Since Jim, the clerk, made a mistake in charging too much, Pamela received a rebate for the overcharge.
2. A discount or deduction on a sales price: Heather received a rebate for the new computer because she was a university student and students were offered rebates if they bought their laptops before a specified date.
3. A return of part of an original payment for some service or merchandise: Albert received a partial rebate for buying so many clothes.
4. To lower the amount or rate of something; such as, a tax: Ryan received a rebate after filing his tax return.
5. Etymology: "to deduct, subtract" comes from Old French rabattre, "to beat down, to drive back"; also "deduct", from re-, "repeatedly" + abattre, "to beat down".

The meaning "to pay back (a sum) as a rebate" is believed to come from about 1957.