(1) A value or reference passed to a function, command, or program that serves as input or controls actions. The value is supplied by a user or by another program or process.
(2) In the Reusable Asset Specification (RAS), an extension point that is viewed on a collaboration. The parameter can have type and default value information as part of its description. See also parameterized collaboration.
(3) In UML modeling, a specific argument that passes information between behavioral features of models, such as operations.