A row on a business process diagram. A way of indicating who is responsible for a given process or activity. Swimlanes are named on the left side of the process diagram. In most cases swimlanes are assigned to departments, groups within departments, individuals, or to applications, systems of applications or databases. In exceptional cases, swimlanes may represent geographical regions. Processes, sub-processes or activities that fall within a given swimlane are the responsibility of the entity named on the left axis of the process diagram. (Some workflow tools represent swimlanes as vertical columns, effectively rotating the process diagrams 90 degrees. The distinction between horizontal or vertical swimlanes is arbitrary.)

a partition on an activity diagram used to organize responsibilities for activities

a visual mechanism of organizing different activities into categories of the same functionality

a process role