A person who believes in or practices ditheism; someone who acknowledges two gods or two equal divine powers.
From ditheism + '-ist' (one who practices or believes). The '-ist' suffix specifically marks someone as an adherent of the doctrine.
Ancient Zoroastrians were arguably history's most sophisticated ditheists, developing an entire theology around how Ahura Mazda (good) eternally struggles against Ahriman (evil)—influencing Judaism, Christianity, and Islam later.
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