demon has definitions from the field of folklore
1
[ noun ] (folklore) one of the evil spirits of traditional Jewish and Christian belief

Used in print

(William G. Pollard, Physicist and Christian....)

Demons , fairies , angels , and a host of other spiritual_beings were as much a part of the experiential world of western man as were rocks and trees and stars .

For all involved in this discussion the devil is a real entity who can really be confronted in the woods on a dark night , the demon world is populated with real creatures , and witches actually can be seen flying through the air .

(Clayton C. Barbeau, The Ikon....)

Clumps of brush that they passed were so many enchained demons straining in anger to tear and gnaw on his bones .

2
[ noun ] someone extremely diligent or skillful

Examples

"he worked like a demon to finish the job on time" "she's a demon at math"

Related terms

actor

3
[ noun ] a cruel wicked and inhuman person

Synonyms

fiend ogre devil monster

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