gallstone vs calculus

gallstone and calculus both are nouns.

Word	Noun	Adjective	Verb	Adverb
gallstone	Yes	No	No	No
calculus	Yes	No	No	No

As nouns, calculus is a hypernym of gallstone; that is, calculus is a word with a broader meaning than gallstone:

gallstone: a calculus formed in the gall bladder or its ducts
calculus: a hard lump produced by the concretion of mineral salts; found in hollow organs or ducts of the body

Other hypernyms of gallstone include concretion.

gallstone (noun)	calculus (noun)
a calculus formed in the gall bladder or its ducts	the branch of mathematics that is concerned with limits and with the differentiation and integration of functions
	a hard lump produced by the concretion of mineral salts; found in hollow organs or ducts of the body
	an incrustation that forms on the teeth and gums