credit card

plastic card with a magnetic strip given to a customer by a bank or other business for the purpose of making purchases on credit, charge card, charge plate

A credit card is a system of payment named after the small plastic card issued to users of the system. A credit card is different from a debit card in that it does not remove money from the user's account after every transaction. In the case of credit cards, the issuer lends money to the consumer (or the user). It is also different from a charge card (though this name is sometimes used by the public to describe credit cards), which requires the balance to be paid in full each month. In contrast, a credit card allows the consumer to 'revolve' their balance, at the cost of having interest charged. Most credit cards are the same shape and size, as specified by the ISO 7810 standard.
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Noun
1. a card (usually plastic) that assures a seller that the person using it has a satisfactory credit rating and that the issuer will see to it that the seller receives payment for the merchandise delivered
(synonym) charge card, charge plate
(hypernym) open-end credit, revolving credit, charge account credit
(hyponym) bank card
(part-meronym) magnetic stripe

a small card, usually of plastic, used to obtain consumer products without immediate payment; the card is issued by a financial institution on the understanding that the consumer repays sums spent against the card with interest.