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fiend

[feend] / find /
NOUN
dastardly person
Synonyms
STRONGEST
barbarian ogre
STRONG
Mephistopheles Satan beast brute demon devil hellion imp monster serpent troll
WEAK
diablo evil spirit little devil
Antonyms
STRONG
angel god
NOUN
person excessively interested in something
Synonyms
STRONGEST
aficionado fanatic freak maniac
STRONG
addict bug bum devotee enthusiast fan monomaniac nut votary zealot
WEAK
bigot votarist

From Roget's 21st Century Thesaurus, Third Edition Copyright © 2013 by the Philip Lief Group.