redness vs chromatic color

redness and chromatic color both are nouns.

Word	Noun	Adjective	Verb	Adverb
redness	Yes	No	No	No
chromatic color	Yes	No	No	No

As nouns, chromatic color is a hypernym of redness; that is, chromatic color is a word with a broader meaning than redness:

redness: red color or pigment; the chromatic color resembling the hue of blood
chromatic color: a color that has hue

Other hypernyms of redness include chromatic colour, spectral color, spectral colour.

redness (noun)	chromatic color (noun)
red color or pigment; the chromatic color resembling the hue of blood	a color that has hue
a response of body tissues to injury or irritation; characterized by pain and swelling and redness and heat