physiology vs erect

physiology is a noun but erect is not a noun.

Word	Noun	Adjective	Verb	Adverb
physiology	Yes	No	No	No
erect	No	Yes	Yes	No

physiology (noun)	erect (noun)
processes and functions of an organism
the branch of the biological sciences dealing with the functioning of organisms

physiology (adjective)	erect (adjective)
	upright in position or posture
	of sexual organs; stiff and rigid

physiology (verb)	erect (verb)
	construct, build, or erect
	cause to rise up