One who animadverts; a person who makes critical remarks, censures, or passes disapproving judgment.
From 'animadvert' plus '-er' suffix creating an agent noun. Someone who performs the action of turning their mind toward faults.
An 'animadverter' is someone whose role is to critique—like a critic or reviewer—so the word itself brands them as a professional fault-finder, which isn't quite a compliment.
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