fiendish

[feen-dish]

adjective

1. diabolically cruel and wicked.

fiendish

/ ˈfiːndɪʃ /

adjective

1. of or like a fiend

2. diabolically wicked or cruel

3. informal,  extremely difficult or unpleasant

   a fiendish problem

Other Word Forms

• fiendishly adverb
• fiendishness noun

Word History and Origins

Origin of fiendish¹

First recorded in 1520–30; fiend + -ish ¹

Example Sentences

That is good news for Inter who have a fiendish run of fixtures to close their league phase campaign, including clashes at the San Siro with Liverpool and Premier League leaders Arsenal.

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Atencio’s fiendish feline would have followed guests throughout the ride, a creature said to despise living humans and with predatory, possessive instincts.

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Easy enough - except our celebrities had to navigate through a fiendish array of red laser beams, all pointing at awkward angles, meaning the most nimble had the easiest time of it.

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From the celebration of the deceased known as Día de los Muertos, to the foreboding thrills and life lessons underpinning Latin America’s fiendish folklore, spooky things are as revered as they are feared.

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But drawing players away from multiplayer behemoths like Fortnite and Call of Duty has proved, for others at least, to be a challenge more fiendish than even FromSoftware could dream up.

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Related Words

• brutish 
• nefarious