spelaeology vs geology

spelaeology and geology both are nouns.

Word	Noun	Adjective	Verb	Adverb
spelaeology	Yes	No	No	No
geology	Yes	No	No	No

As nouns, geology is a hypernym of spelaeology; that is, geology is a word with a broader meaning than spelaeology:

spelaeology: the scientific study of caves
geology: a science that deals with the history of the earth as recorded in rocks

spelaeology (noun)	geology (noun)
the pastime of exploring caves	a science that deals with the history of the earth as recorded in rocks
the scientific study of caves