10 U.S.C. § 3401

In this chapter: (1) Delivery order contract .— The term “delivery order contract” means a contract for property— (A) that does not procure or specify a firm quantity of property (other than a minimum or maximum quantity); and (B) that provides for the issuance of orders for the delivery of property during the period of the contract. (2) Task order contract .— The term “task order contract” means a contract for services— (A) that does not procure or specify a firm quantity of services (other than a minimum or maximum quantity); and (B) that provides for the issuance of orders for the performance of tasks during the period of the contract.