tumidity vs swelling

tumidity and swelling both are nouns.

Word	Noun	Adjective	Verb	Adverb
tumidity	Yes	No	No	No
swelling	Yes	No	No	No

As nouns, swelling is a hypernym of tumidity; that is, swelling is a word with a broader meaning than tumidity:

Other hypernyms of tumidity include lump, puffiness.

tumidity (noun)	swelling (noun)
slight swelling of an organ or part	the increase in volume of certain substances when they are heated (often accompanied by release of water)
	something that bulges out or is protuberant or projects from its surroundings
	an abnormal protuberance or localized enlargement