voucher

n. certificate that bears monetary value, coupon; receipt; authorizer, endorser

A voucher is a bond which is worth a certain monetary value and which may only be spent for specific reasons or on specific goods. Examples include — but are not limited to — housing and food vouchers. 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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Noun
1. someone who vouches for another or for the correctness of a statement
(synonym) verifier
(hypernym) supporter, protagonist, champion, admirer, booster, friend
(derivation) guarantee, vouch
2. a document that serves as evidence of some expenditure
(hypernym) document, written document, papers
3. a negotiable certificate that can be detached and redeemed as needed
(synonym) coupon
(hypernym) commercial document, commercial instrument
(hyponym) book token

n. voucher

n. coupon