(1) In a federated database system, a description of a data source.
(2) One or more WSDL files that describe a service. Service definitions are produced by the Definition, Deployment, Adaptor, Skeleton, and Proxy wizards.
(3) An explicit definition of all the workloads and processing capacity in a sysplex. A service definition includes service policies, workloads, service classes, resource groups, and classification rules.