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fiendish

[ feen-dish ]
/ ˈfin dɪʃ /
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See synonyms for: fiendish / fiendishly / fiendishness on Thesaurus.com

adjective

diabolically cruel and wicked.

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Origin of fiendish

First recorded in 1520–30; fiend + -ish1
fiend·ish·ly, adverbfiend·ish·ness, noun
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2021

British Dictionary definitions for fiendish

fiendish
/ (ˈfiːndɪʃ) /

adjective

of or like a fiend
diabolically wicked or cruel
informal extremely difficult or unpleasanta fiendish problem
fiendishly, adverbfiendishness, noun
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
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