The abstract syntax of UML is specified using a UML model called the UML metamodel. Classes in a metamodel are called metaclasses. 

The metaclass icon in the Model Browser is . Its shape is displayed with «metaclass» stereotype.

All metaclasses in our modeling tools are stored in the Auxiliary Resources, expand the UML Standard Profile Package > UML 2 Metamodel Package.

To show the auxiliary resources

  • In the Model Browser, click and enable the Show Auxiliary Resources option.