optical density vs denseness

optical density and denseness both are nouns.

Word	Noun	Adjective	Verb	Adverb
optical density	Yes	No	No	No
denseness	Yes	No	No	No

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

optical density: (physics) a measure of the extent to which a substance transmits light or other electromagnetic radiation
denseness: the amount per unit size

Other hypernyms of optical density include density.

optical density (noun)	denseness (noun)
(physics) a measure of the extent to which a substance transmits light or other electromagnetic radiation	the amount per unit size
	the spatial property of being crowded together
	the quality of being mentally slow and limited