diabolically cruel and wicked.

Origin of fiendish

First recorded in 1520–30; fiend + -ish1
Related formsfiend·ish·ly, adverbfiend·ish·ness, noun Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for fiendish

Contemporary Examples of fiendish

Historical Examples of fiendish

  • No wonder he is sometimes provoked to fiendish outbursts of wrath.

  • All that fiendish cruelty and the demon of destruction could do was done.

    The Roof of France

    Matilda Betham-Edwards

  • What was it—madness, a nightmare, or a trap into which he had been decoyed with fiendish artfulness?

    The Secret Agent

    Joseph Conrad

  • This language is wanton cruelty,—it is fiendish insult,—is it not, Evelyn?

  • So avenged I their fiendish deeds death-fall of Danes, as was due and right.



British Dictionary definitions for fiendish



of or like a fiend
diabolically wicked or cruel
informal extremely difficult or unpleasanta fiendish problem
Derived Formsfiendishly, 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

Word Origin and History for fiendish

1520s, from fiend + -ish. Related: Fiendishly; fiendishness.

Online Etymology Dictionary, © 2010 Douglas Harper