overshadow vs overlook

overshadow is not a noun while overlook is a noun.

Word	Noun	Adjective	Verb	Adverb
overshadow	No	No	Yes	No
overlook	Yes	No	Yes	No

As verbs, overlook is a hypernym of overshadow; that is, overlook is a word with a broader meaning than overshadow:

Other hypernyms of overshadow include command, dominate, overtop.

overshadow (noun)	overlook (noun)
	a high place affording a good view

overshadow (verb)	overlook (verb)
cast a shadow upon	leave undone or leave out
be greater in significance than	watch over
make appear small by comparison	look past, fail to notice
	look down on
	be oriented in a certain direction