critic vs authenticator

critic and authenticator both are nouns.

Word	Noun	Adjective	Verb	Adverb
critic	Yes	No	No	No
authenticator	Yes	No	No	No

As nouns, authenticator is a hyponym of critic; that is, authenticator is a word with a more specific, narrower meaning than critic:

critic: anyone who expresses a reasoned judgment of something
authenticator: one who determines authenticity (as of works of art) or who guarantees validity

critic (noun)	authenticator (noun)
a person who is professionally engaged in the analysis and interpretation of works of art	one who determines authenticity (as of works of art) or who guarantees validity
anyone who expresses a reasoned judgment of something
someone who frequently finds fault or makes harsh and unfair judgments