epidemic vs pestiferous

epidemic is a noun but pestiferous is not a noun.

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

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

epidemic (adjective)	pestiferous (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
	tending to corrupt or pervert
	contaminated with infecting organisms