great vs greatness

great and greatness both are nouns.

Word	Noun	Adjective	Verb	Adverb
great	Yes	Yes	No	No
greatness	Yes	No	No	No

great (noun)	greatness (noun)
a person who has achieved distinction and honor in some field	the property possessed by something or someone of outstanding importance or eminence
	unusual largeness in size or extent or number

great (adjective)	greatness (adjective)
excellent
in an advanced stage of pregnancy
uppercase
remarkable or out of the ordinary in degree or magnitude or effect
of major significance or importance
relatively large in size or number or extent; larger than others of its kind