A rebate is a partial refund of the cost of an item. It acts as an incentive to help sell the product. If your new cell phone came with a rebate, you'll get a check in the mail for a certain amount of the cost.
A well-known rebate occurred in 2007 when President George Bush issued tax rebate checks to many people in America, giving back some of what each person paid in taxes. Rebate comes from the Old French word rabattre, meaning "beat down, drive back." Rebate can also be used as a verb that refers to giving a reduction in price during a sale. For example, your internet provider might rebate your bill for three months to keep you as a customer.