diapir vs geological formation

diapir and geological formation both are nouns.

Word	Noun	Adjective	Verb	Adverb
diapir	Yes	No	No	No
geological formation	Yes	No	No	No

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

diapir: a domed rock formation where a core of rock has moved upward and pierced through the more brittle overlying strata
geological formation: (geology) the geological features of the earth

Other hypernyms of diapir include formation.

diapir (noun)	geological formation (noun)
a domed rock formation where a core of rock has moved upward and pierced through the more brittle overlying strata	(geology) the geological features of the earth