geology vs orology

geology and orology both are nouns.

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

As nouns, orology is a hyponym of geology; that is, orology is a word with a more specific, narrower meaning than geology:

geology: a science that deals with the history of the earth as recorded in rocks
orology: the science of mountains

geology (noun)	orology (noun)
a science that deals with the history of the earth as recorded in rocks	the science of mountains