fiend has definitions from the field of folklore
1
[ noun ] a cruel wicked and inhuman person

Synonyms

devil demon ogre monster

Used in print

(Marvin Schiller, "The Sheep's in the Meadow,"...)

I looked_for Jessica to materialize out of the clogging , curdling crowd and , as the time passed and I waited , a fiend came_to_life beside me and whispered in my ear : How was I planning to greet Jessica ?

2
[ noun ] (folklore) one of the evil spirits of traditional Jewish and Christian belief
3
[ noun ] a person motivated by irrational enthusiasm (as for a cause)

Synonyms

fanatic

Examples

"A fanatic is one who can't change his mind and won't change the subject"--Winston Churchill

Related terms

enthusiast

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