A person who worships demons; someone who practices demonolatry or demon-worship as a religious devotion.
From demon + -olater (from Latin 'latria' meaning worship or service, from 'latere' to serve). The -olater suffix creates agent nouns for people who worship specific things, as in idolater.
Demonolaters were often accused rather than self-identified—religious authorities called heretics and witches 'demonolaters' as a charge, making the word itself a tool of religious persecution and power rather than a genuine self-description.
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