1. Commerce: A confirmed request by one party to another to buy, sell, deliver, or receive goods or services under specified terms and conditions. When accepted by the receiving party, an order becomes a legally binding contract. See also purchase order.
2. Banking: An instrument (such as a check or draft) through which its maker or issuer (drawer) authorizes a bank or other financial institution to pay the stated sum to a named holder (drawee or payee). Such instruments are transferable by endorsement, and thus are negotiable instruments.
3. Law: An authoritative mandate, command, or direction issued by a court under its seal. A final court order is called judgment.