catarrh vs redness

catarrh and redness both are nouns.

Word	Noun	Adjective	Verb	Adverb
catarrh	Yes	No	No	No
redness	Yes	No	No	No

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

catarrh: inflammation of the nose and throat with increased production of mucus
redness: a response of body tissues to injury or irritation; characterized by pain and swelling and redness and heat

Other hypernyms of catarrh include inflammation, rubor.

catarrh (noun)	redness (noun)
inflammation of the nose and throat with increased production of mucus	red color or pigment; the chromatic color resembling the hue of blood
	a response of body tissues to injury or irritation; characterized by pain and swelling and redness and heat