Voucher

A voucher is a bond which is worth a certain monetary value and which may be redeemed only for specific reasons or on specific goods.
Examples include housing, travel, and meal vouchers.
Vouchers are a form of scrip.
The term voucher is also a synonym for receipt and is often used to refer to receipts used as evidence of, for example, the declaration that a service has been performed or that an expenditure has been made.

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