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he·re·si·arch

(hə-rēzē-ärk′, hĕrĭ-sē-)

One who originates or is the chief proponent of a heresy or heretical movement.

[Late Latin haeresiarcha, from Late Greek hairesiarkhēs : Greek hairesis, sect; see HERESY + Greek -arkhēs, -arch.]

Indo-European & Semitic Roots Appendices

Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:

Indo-European Roots

Semitic Roots

The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.

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