nudnick vs pesterer

nudnick and pesterer both are nouns.

Word	Noun	Adjective	Verb	Adverb
nudnick	Yes	No	No	No
pesterer	Yes	No	No	No

As nouns, pesterer is a hypernym of nudnick; that is, pesterer is a word with a broader meaning than nudnick:

Other hypernyms of nudnick include bore, dullard, blighter, cuss, gadfly, pest.

nudnick (noun)	pesterer (noun)
(Yiddish) someone who is a boring pest	a persistently annoying person