jejunitis vs redness

jejunitis and redness both are nouns.

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

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

jejunitis: inflammation of the jejunum of the small intestine
redness: a response of body tissues to injury or irritation; characterized by pain and swelling and redness and heat

Other hypernyms of jejunitis include inflammation, rubor.

jejunitis (noun)	redness (noun)
inflammation of the jejunum of the small intestine	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