In the application that I'm currently developing the UI for, the menu consists of sub menus that each have a heading. For this I'm using description lists but would like to add aria roles to the menu components. There doesn't seem to be a role for menu headings in the spec. Below is an example layout. Any thoughts on the correct role? Labeled-by doesn't seem to cut it but maybe that's correct.
<dl role="menubar">
<dt role="menuitem">Item One</dt>
<dt role="menuitem">Item Two</dt>
<dd>
<dl role="menu">
<dt role="???">Sub menu</dt>
<dd role="menuitem">Item One</dd>
<dd role="menuitem">Item Two</dd>
</dl>
</dd>
</dl>