epidemic vs plaguey

epidemic is a noun but plaguey is not a noun.

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

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

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

epidemic (adverb)	plaguey (adverb)
	in a pernicious or annoying manner