A person, usually a judge or official, who makes official decisions and judgments in disputes or legal cases.
From adjudicate plus -or, a suffix creating agent nouns (words for people who do things). This term emerged to describe anyone with formal authority to decide cases, not just judges.
An 'adjudicator' could be a judge, an arbitrator, or even a school official settling disputes—basically anyone with the official power to hear both sides and make a binding decision that sticks.
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