How can I add an Accordion menu in WordPress?
Here’s an example of what an Accordion menu looks like and how it works. This menu is set to expand on mouseover. As soon as you point your mouse pointer over a title the menus expands displaying the submenus. It could also be set to on-click which means that to expand and display the submenu you have to click on a title.
You could also add it to the Sidebar and don't necessarily have to use it as a menu.