volcanic crater vs formation

volcanic crater and formation both are nouns.

Word	Noun	Adjective	Verb	Adverb
volcanic crater	Yes	No	No	No
formation	Yes	No	No	No

As nouns, formation is a hypernym of volcanic crater; that is, formation is a word with a broader meaning than volcanic crater:

Other hypernyms of volcanic crater include geological formation.

volcanic crater (noun)	formation (noun)
a bowl-shaped geological formation at the top of a volcano	the act of fabricating something in a particular shape
	the act of forming or establishing something
	creation by mental activity
	a particular spatial arrangement
	an arrangement of people or things acting as a unit
	(geology) the geological features of the earth
	natural process that causes something to form