density vs tightness

density and tightness both are nouns.

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

As nouns, density and tightness are synonyms defined as:

Other synonyms of density include compactness, concentration, denseness.

density (noun)	tightness (noun)
the amount per unit size	lack of movement or room for movement
the spatial property of being crowded together	extreme stinginess
	the spatial property of being crowded together
	a tight feeling in some part of the body
	a state occasioned by scarcity of money and a shortage of credit