plague vs harass

plague is a noun but harass is not a noun.

Word	Noun	Adjective	Verb	Adverb
plague	Yes	No	Yes	No
harass	No	No	Yes	No

As verbs, plague and harass are synonyms defined as:

Other synonyms of plague include beset, chevvy, chevy, chivvy, chivy, harry, hassle, molest, provoke.

plague (noun)	harass (noun)
an annoyance
any large scale calamity (especially when thought to be sent by God)
a swarm of insects that attack plants
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
any epidemic disease with a high death rate

plague (verb)	harass (verb)
annoy continually or chronically	exhaust by attacking repeatedly
cause to suffer a blight	annoy continually or chronically