A demon is an evil, mythical monster or spirit. Stories about demons are featured in a variety of different religious traditions.

You might come across a demon in a supernatural fairy tale, or even in the Christian Bible. Demons are often interchangeable with devils, and both words are sometimes used to talk about a cruel, fiendish person. If you're extremely good at something, you also might be described as a demon: "She's a demon at bowling." The Greek root, daimon, doesn't have the same negative connotations — it means "spirit or deity."

Definitions of demon
  1. noun
    an evil supernatural being
    synonyms: daemon, daimon, devil, fiend
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    a male demon believed to visit people while they sleep and to consort with sleeping women
    succuba, succubus
    a female demon believed to have sexual intercourse with sleeping men
    dibbuk, dybbuk
    (Jewish folklore) a demon that enters the body of a living person and controls that body's behavior
    type of:
    evil spirit
    a spirit tending to cause harm
  2. noun
    a cruel, wicked, and inhuman person
    synonyms: devil, fiend, monster, ogre
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    someone who acts as if possessed by a demon
    type of:
    disagreeable person, unpleasant person
    a person who is not pleasant or agreeable
  3. noun
    someone extremely diligent or skillful
    “he worked like a demon to finish the job on time”
    “she's a demon at math”
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    type of:
    actor, doer, worker
    a person who acts and gets things done
Word Family

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