A person who expiscates; someone skilled at discovering or extracting hidden information, secrets, or truth through questioning or investigation.
From expiscate + -or suffix (Latin agent noun). The term literally means 'one who fishes out' but applies to anyone who skillfully extracts information.
An expiscator is essentially a truth-fisher—whether it's Socrates using questions to draw out ideas or a prosecutor extracting confessions, they're all expiscators in disguise!
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