ABA Routing Number: Also referred to as Transit Routing Number. Directs electronic ACH deposits to the proper bank institution.

ACH: Automated Clearing House. A regional organization used by member banks to electronically transfer funds between members.

ACH Network: A central distribution and settlement point for electronic items exchanged among depository financial institutions.

ACH Operator: A central clearing facility, operated by a Federal Reserve Bank or a private sector organization on behalf of depository financial institutions, in which participating financial institutions transmit or receive ACH entries.

AMEX: Abbreviation for American Express, an organization that issues travel and entertainment cards and acquires transactions.

AVS: See Address Verification.

Access Provider: A company that provides its customers a service to access the Internet. The user normally connects to the access provider's server via a modem using a dial-up connection.

Account Number: A unique sequence of numbers assigned to a cardholder account that identifies the issuer and type of financial transaction card.

Acquirer: A licensed member of MasterCard and/or VISA (or its agent) which maintains merchant relationships, receives all bankcard transactions from the merchant, and initiates that data into an interchange system.

Acquiring Bank/Merchant Bank: The bank that does business with merchants enabling them to accept credit cards. A merchant has an account with this bank and each day deposits the value of the day's credit card sales.Acquirers buy (acquire) the merchant's sales slips and credit the tickets' value to the merchant's account.

Acquiring Processor: The processor provides credit card processing, billing, reporting and settlement, and operational services to the acquirer. Many financial institutions hire a third party for more cost-effective bankcard processing.

Address Verification (AVS): A service provided through merchant services in which the merchant verifies the cardholder's address. Primarily used by mail/telephone order merchants to combat fraud. Not a guarantee that a transaction is valid.

Affinity Card: A credit card issued in conjunction with an organization or collective group; for example, profession, alumni, retired persons association. The card issuer often pays the organization a royalty.

Altered Card: A card on which the original embossed or encoded information has been altered for fraudulent purposes.

Arbitration: The procedure used to determine responsibility for a chargeback-related dispute between two members.

Assessments: Fees paid quarterly by members to VISA and MasterCard to support marketing and operating activities.

Association: An organization owned by members, which services and obtains processing services for members and functions as a principal/proprietary member of VISA or MasterCard.

Authorization: The act of ensuring the cardholder has adequate funds available against his or her line of credit. A positive authorization results in an authorization code being generated, and those funds being set aside. The cardholder's available credit limit is reduced by the authorized amount.

Authorization Approval Card: The numerical code designated by the issuer, given to a sales transaction as verification that the sale has been authorized. The authorization code is always included on the merchant sales draft.

Auto Representment: Chargebacks (credit not issued, transaction not authorized, etc.) that were automatically resolved by processor on the merchant's behalf without their knowledge or intervention.

Automated Bill Payment: The crediting of funds from a consumer's account to a company's account for the payment of a consumer's bill or obligation.

Available Credit: The difference between a cardholder's credit limit and the present balance on the account, including outstanding transactions not yet received through interchange.

Average Ticket: The average size of a merchant bankcard transaction. Generally used in pricing decisions and calculations.