composite
A widget that may contain navigable descendants or owned children.
Abstract roles are the foundation upon which all other WAI-ARIA roles are built. Content authors MUST NOT use abstract roles because they are not implemented in the API binding.
Description
A widget that may contain navigable descendants or owned children
Authors SHOULD ensure that a composite widget exists as a single navigation stop within the larger navigation system of the web page. Once the composite widget has focus, authors SHOULD provide a separate navigation mechanism for users to navigate to elements that are descendants or owned children of the composite element.
Note: composite is an abstract role. Authors should not use this role in content.
Characteristics
Reference