demon

n. evil spirit; devil, fiend; mischievous person, troublemaker (especially a child)

In religion, folklore, and mythology a demon (or daemon, dæmon, daimon from Greek: δαίμων [ðaïmon]) is a supernatural being that has generally been described as a malevolent spirit, and in Christian terms it is generally understood as a  Fallen angel, formerly of God. A demon is frequently depicted as a force that may be conjured and insecurely controlled. The "good" demon in recent use is largely a literary device (e.g., Maxwell's demon), though references to good demons can be found in Hesiod and Shakespeare. In common language, to "demonize" a person means to characterize or portray them as evil, or as the source of evil.
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Noun
1. one of the evil spirits of traditional Jewish and Christian belief
(synonym) devil, fiend, daemon, daimon
(hypernym) evil spirit
(hyponym) incubus
(derivation) demonize, demonise
2. a cruel wicked and inhuman person
(synonym) monster, fiend, devil, ogre
(hypernym) unpleasant person, disagreeable person
(hyponym) demoniac
(derivation) demonize, demonise
3. someone extremely diligent or skillful; "he worked like a demon to finish the job on time"; "she's a demon at math"
(hypernym) actor, doer, worker

n. demon, daemon, fiend, devil

n. demon, evil spirit; devil, fiend