overtop vs shadow

overtop is not a noun while shadow is a noun.

Word	Noun	Adjective	Verb	Adverb
overtop	No	No	Yes	No
shadow	Yes	No	Yes	No

As verbs, shadow is a hyponym of overtop; that is, shadow is a word with a more specific, narrower meaning than overtop:

Other hyponyms of overtop include dwarf, overshadow.

overtop (noun)	shadow (noun)
	refuge from danger or observation
	something existing in perception only
	an indication that something has been present
	a premonition of something adverse
	an unilluminated area
	a spy employed to follow someone and report their movements
	an inseparable companion
	a dominating and pervasive presence
	shade within clear boundaries

overtop (verb)	shadow (verb)
look down on	follow, usually without the person's knowledge
	make appear small by comparison
	cast a shadow over