geology vs structural

geology is a noun but structural is not a noun.

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

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

geology (adjective)	structural (adjective)
	relating to or having or characterized by structure
	relating to or caused by structure, especially political or economic structure
	relating to or concerned with the morphology of plants and animals
	pertaining to geological structure
	concerned with systematic structure in a particular field of study
	affecting or involved in structure or construction