A person who is devoted to doctrines and principles, especially one who adheres rigidly to them without flexibility.
From doctrine + -arian (from Latin -arius 'relating to, connected with'). The -arian suffix (as in vegetarian, humanitarian) identifies someone associated with or devoted to a particular principle or practice.
A 'doctrinarian' is essentially someone who loves doctrines—but the word carries judgment built in, implying they love them too much and too rigidly, showing how language subtly shapes how we view different worldviews.
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