density vs compactness

density and compactness both are nouns.

Word	Noun	Adjective	Verb	Adverb
density	Yes	No	No	No
compactness	Yes	No	No	No

As nouns, compactness is a hypernym of density; that is, compactness is a word with a broader meaning than density:

As nouns, density and compactness are synonyms defined as:

Other synonyms of density include concentration, denseness, tightness.

density (noun)	compactness (noun)
the amount per unit size	the spatial property of being crowded together
the spatial property of being crowded together	the consistency of a compact solid