pestilence vs pestilential

pestilence is a noun but pestilential is not a noun.

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

pestilence (noun)	pestilential (noun)
a pernicious and malign influence that is hard to get rid of
any epidemic disease with a high death rate
a serious (sometimes fatal) infection of rodents caused by Yersinia pestis and accidentally transmitted to humans by the bite of a flea that has bitten an infected animal

pestilence (adjective)	pestilential (adjective)
	likely to spread and cause an epidemic disease