judge vs arbitrator

judge and arbitrator both are nouns.

Word	Noun	Adjective	Verb	Adverb
judge	Yes	No	Yes	No
arbitrator	Yes	No	No	No

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

Other hyponyms of judge include appraiser, valuator, arbiter, umpire, critic.

judge (noun)	arbitrator (noun)
a public official authorized to decide questions brought before a court of justice	someone chosen to judge and decide a disputed issue
an authority who is able to estimate worth or quality

judge (verb)	arbitrator (verb)
form a critical opinion of
judge tentatively or form an estimate of (quantities or time)
determine the result of (a competition)
pronounce judgment on
put on trial or hear a case and sit as the judge at the trial of