geology vs incumbent

geology and incumbent both are nouns.

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

geology (noun)	incumbent (noun)
a science that deals with the history of the earth as recorded in rocks	the official who holds an office

geology (adjective)	incumbent (adjective)
	currently holding an office
	necessary (for someone) as a duty or responsibility; morally binding
	lying or leaning on something else