maligner vs vilifier

maligner and vilifier both are nouns.

Word	Noun	Adjective	Verb	Adverb
maligner	Yes	No	No	No
vilifier	Yes	No	No	No

As nouns, maligner and vilifier are synonyms defined as:

maligner and vilifier: one who attacks the reputation of another by slander or libel

Other synonyms of maligner include backbiter, defamer, libeler, slanderer, traducer.

maligner (noun)	vilifier (noun)
one who attacks the reputation of another by slander or libel	one who attacks the reputation of another by slander or libel