Manichean

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From our dictionary:
Man•i•che•an

(man"i-kē'un), —n.
Also, Man•i•chee (man'i-kē").
an adherent of the dualistic religious system of Manes, a combination of Gnostic Christianity, Buddhism, Zoroastrianism, and various other elements, with a basic doctrine of a conflict between light and dark, matter being regarded as dark and evil.

—adj.
of or pertaining to the Manicheans or their doctrines.
Also, Man"i•chae'an.