epididymitis vs redness

epididymitis and redness both are nouns.

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

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

epididymitis: painful inflammation of the epididymis
redness: a response of body tissues to injury or irritation; characterized by pain and swelling and redness and heat

Other hypernyms of epididymitis include inflammation, rubor.

epididymitis (noun)	redness (noun)
painful inflammation of the epididymis	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