blepharitis vs redness

blepharitis and redness both are nouns.

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

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

blepharitis: inflammation of the eyelids characterized by redness and swelling and dried crusts
redness: a response of body tissues to injury or irritation; characterized by pain and swelling and redness and heat

Other hypernyms of blepharitis include inflammation, rubor.

blepharitis (noun)	redness (noun)
inflammation of the eyelids characterized by redness and swelling and dried crusts	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