FIENDISH Synonyms: 107 Similar and Opposite Words

fiendish

adjective

ˈfēn-dish

Definition of fiendish

as in demonic

of, relating to, or worthy of an evil spirit a fiendish delight in playing cruel tricks

Synonyms & Similar Words

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Antonyms & Near Antonyms

as in brutal

having or showing the desire to inflict severe pain and suffering on others shook with fiendish laughter as he watched his victims writhe in agony

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Antonyms & Near Antonyms

Example Sentences

Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.

Recent Examples of fiendish Across the short films, Early plays, among other roles, a smiling, fiendish mall pop act; the shy, offbeat child of an overbearing stage mom; and an extra in a makeup chair whose instruments, his face and his voice, are progressively hampered by prosthetics. — Lauren Michele Jackson, New Yorker, 7 June 2026 Plotting kind of my most fiendish, happy, mad scientist state. — Literary Hub, 4 May 2026 The soloist in the Sibelius was a mediocre violinist ill-equipped to deal with the concerto’s profound emotions and fiendish technical demands. — Luis Palomares, Miami Herald, 27 Feb. 2026 Jim Carrey plays the eponymous Grinch, a fiendish Whoville outlaw who declares war on the festive season. — Danny Horn, Entertainment Weekly, 29 Nov. 2025 See All Example Sentences for fiendish

Recent Examples of Synonyms for fiendish

Adjective

The better to act out empire’s idea of what disgusting demonic sickness looks like.

— Literary Hub, Literary Hub, 15 Sep. 2026
Around his ankle is a heavy plastic GPS tracking device, with a red, LED status light glaring like a demonic eye.

— Philip Kennicott, Washington Post, 5 Sep. 2026

Definition of demonic

Adjective

Horror films and increasingly brutal crime stories reveal the very large market for the subject.

— Literary Hub, Literary Hub, 18 Sep. 2026
McKinley stages a few bullet-sweating sequences of peril, including a particularly brutal transport of gold bars across a crumbling rope bridge and an underwater accident exacerbated by floating logs.

— Katie Walsh, Los Angeles Times, 18 Sep. 2026

Definition of brutal

Adjective

Fiction and reality braid in clever ways as Highsmith ridicules her visitor and is inspired by him, imagining a sinister plot (which could in fact be real).

— Taylor Antrim, Vogue, 19 Sep. 2026
Link shifts from a charming oddball as Whatsit to a sinister figure on the planet of Camazotz.

— Emily McClanathan, Chicago Tribune, 15 Sep. 2026

Definition of sinister

Adjective

Bronwyn’s mother, Muzzy, who was lambasted all of last season for being cold and arguably cruel to her daughter, is notably softer in her first scene back — though the bob is as cunty as ever.

— Tom Smyth, Vulture, 17 Sep. 2026
He was convicted of four counts of war crimes including murder, torture, cruel treatment and arbitrary detention.

— Arkansas Online, Arkansas Online, 17 Sep. 2026

Definition of cruel

Adjective

His Lamb goes from a brash Yorkshire showman to a callous profiteer of human vice and misery, his cheeky smile becoming a vicious snarl.

— Joe Reid, Vulture, 21 Sep. 2026
The strikes were often most vicious in the far north of Yemen, a rebel stronghold and the region where the Houthi movement had been founded, in the nineteen-nineties.

— Kareem Fahim, New Yorker, 19 Sep. 2026

Definition of vicious

Adjective

The technique has similarities to web skimming, where malicious code captures payment information as a shopper types it into an online checkout page.

— Kurt Knutsson, FOXNews.com, 18 Sep. 2026
This malicious torrent leads to the download of the malware loader.

— Michael Kan, PC Magazine, 17 Sep. 2026

Definition of malicious

Adjective

Hamilton lets down Claire’s savage hauteur; Mays’ eyes glisten with all the regrets of lost love.

— Theater Critic, Los Angeles Times, 16 Sep. 2026
The savage purge since June of high-momentum stocks – dominated by AI hardware and related industrials – has sapped the bullish aggression of traders, helping to reset tactical sentiment toward a more neutral level.

— Michael Santoli, CNBC, 15 Sep. 2026

Definition of savage

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fiendish

fiendishly

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“Fiendish.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/fiendish. Accessed 22 Sep. 2026.

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Synonyms of fiendish

adjective

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