nodding vs biology

nodding is not a noun while biology is a noun.

Word	Noun	Adjective	Verb	Adverb
nodding	No	Yes	No	No
biology	Yes	No	No	No

nodding (noun)	biology (noun)
	the science that studies living organisms
	all the plant and animal life of a particular region
	characteristic life processes and phenomena of living organisms

nodding (adjective)	biology (adjective)
having branches or flower heads that bend downward