For automation interface purposes, the Variable Name property is an attribute of the instance symbol.
This property specifies the variable name of an Operation instance on a Sequence Diagram.
By default, the Variable Name box is blank.
On a Sequence Diagram, the Variable Name is shown as follows:
This property is set on the Options tab of the Property Pages for an Operation Instance (message) on a Sequence Diagram. To view an instance's Property Pages, on the diagram, right-click the item, and then click Instance Properties.
The following section provides information about the items and diagrams for which Variable Name is a property. For more information about an item or diagram, click it.