pestilential vs epidemic

pestilential is not a noun while epidemic is a noun.

Word	Noun	Adjective	Verb	Adverb
pestilential	No	Yes	No	No
epidemic	Yes	Yes	No	No

pestilential (noun)	epidemic (noun)
	a widespread outbreak of an infectious disease; many people are infected at the same time

pestilential (adjective)	epidemic (adjective)
likely to spread and cause an epidemic disease	(especially of medicine) of disease or anything resembling a disease; attacking or affecting many individuals in a community or a population simultaneously