disparagement vs backbiter

disparagement and backbiter both are nouns.

Word	Noun	Adjective	Verb	Adverb
disparagement	Yes	No	No	No
backbiter	Yes	No	No	No

disparagement (noun)	backbiter (noun)
the act of speaking contemptuously of	one who attacks the reputation of another by slander or libel
a communication that belittles somebody or something