A person who defalcates; someone who steals or embezzles money or property that has been entrusted to their management.
From 'defalcate' plus the agent suffix '-or' (one who does something). The person is literally the one who 'cuts away' funds—the active perpetrator of the financial crime.
The term 'defalcator' is notably rare in modern English because we usually just say 'embezzler,' but the formal version sounds almost scientific, like auditors and lawyers are labeling a specific type of white-collar criminal.
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