demoniac

Use the adjective demoniac to describe something or someone who seems to be possessed by a demon, like the demoniac rantings of the actors portraying scary creatures at the haunted house.

To pronounce demoniac, accent the second syllable: "de-MOE-nee-ac." The word has a somewhat confusing origin. The Latin word daemon means "spirit" and comes from the Greek word daimon, meaning "lesser god" or "guiding spirit." The Christian Greeks, however, translated it as "god of the heathen" and "unclean spirit." It is this negative connotation that is connected to demoniac: "like a demon."

Definitions of demoniac
1

n someone who acts as if possessed by a demon

Type of:
demon, devil, fiend, monster, ogre
a cruel wicked and inhuman person

adj frenzied as if possessed by a demon

Synonyms:
amok, amuck, berserk, demoniacal, possessed
insane
afflicted with or characteristic of mental derangement

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