A person who specializes in ethics; a philosopher or scholar who studies moral principles and how people should behave.
From 'ethic' plus the agent suffix '-ian' (meaning a person who practices or specializes in something), following the pattern of 'physician', 'magician'.
Most philosophers who focus on ethics call themselves 'ethicists,' but 'ethician' is the older, less common term—watching words compete to name the same profession is like watching language evolution in real-time.
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