hierarchical menu vs cascading menu

hierarchical menu and cascading menu both are nouns.

Word	Noun	Adjective	Verb	Adverb
hierarchical menu	Yes	No	No	No
cascading menu	Yes	No	No	No

As nouns, hierarchical menu and cascading menu are synonyms defined as:

hierarchical menu and cascading menu: a secondary menu that appears while you are holding the cursor over an item on the primary menu

Other synonyms of hierarchical menu include submenu.

hierarchical menu (noun)	cascading menu (noun)
a secondary menu that appears while you are holding the cursor over an item on the primary menu	a secondary menu that appears while you are holding the cursor over an item on the primary menu