impressiveness vs grandness

impressiveness and grandness both are nouns.

Word	Noun	Adjective	Verb	Adverb
impressiveness	Yes	No	No	No
grandness	Yes	No	No	No

As nouns, impressiveness and grandness are synonyms defined as:

impressiveness and grandness: splendid or imposing in size or appearance

Other synonyms of impressiveness include magnificence, richness.

impressiveness (noun)	grandness (noun)
splendid or imposing in size or appearance	the quality of being magnificent or splendid or grand
the quality of making a strong or vivid impression on the mind	unusual largeness in size or extent or number
	splendid or imposing in size or appearance
	a prominent status