Acquirer

n. person or thing that acquires; obtainer, person or thing that procures; achiever, attainer, one who gains

An acquirer is a member of MasterCard and/or Visa which maintains merchant relationships and receives all bankcard transactions from the merchant.Acquirers charge the merchants fees which include: a monthly rent for the EFTPOS terminal (if it is not owned by the merchant) which is usually equivalent to around 10 to 30 USD monthly, a percentage fee on their transactions (which varies from country to country, for example in Poland it ranges from 1.8% to 2.5%, regardless of whether the card is debit or credit, in USA and many Western Europe countries the fee is often much lower for debit card transactions, than for those with credit cards), and sometimes--especially in the countries where fees for debit card transactions are much lower--an additional fixed fee per transaction, which ranges from 10 to 20 cents).
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Noun
1. a person who acquires something (usually permanently)
(hypernym) person, individual, someone, somebody, mortal, human, soul
(hyponym) recipient, receiver
(derivation) get, acquire
2. a bank gaining financial control over another financial institution through a payment in cash or an exchange of stock
(hypernym) depository financial institution, bank, banking concern, banking company
(derivation) get, acquire
3. the financial institution that dispenses cash in automated teller machines and collects a fee from the bank that issued the credit card
(hypernym) financial institution, financial organization, financial organisation
(derivation) get, acquire
4. a credit card processing bank; merchants receive credit for credit card receipts less a processing fee
(synonym) merchant bank
(hypernym) depository financial institution, bank, banking concern, banking company
(derivation) get, acquire

(n.)
A person who acquires.
  

A firm or individual that is acquiring something.