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

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
The high-concept thriller stars Valeria Bruni Tedeschi as a demonic character called The Stranger, who entices a young mother played by Jasmine Trinca into forging a Faustian pact.

— Nick Vivarelli, Variety, 3 Sep. 2026

Definition of demonic

Adjective

As Chris, a veteran CIA assassin with terminal cancer whose memory also seems to be going, Malkovich demonstrates a sinister insouciance that at first looks like psycho gloating.

— Bilge Ebiri, Vulture, 3 Sep. 2026
Where does a muse end and something much more sinister begin?

— Literary Hub, Literary Hub, 2 Sep. 2026

Definition of sinister

Adjective

Like her, Americans are also so tired of being screwed by an administration that’s not only grossly incompetent and cruel but corrupt as well.

— Sun Sentinel Editorial Board, Sun Sentinel, 6 Sep. 2026
Rather than heroic, these costly and horribly uncertain stunts come across callous and cruel.

— Richard Lawson, HollywoodReporter, 3 Sep. 2026

Definition of cruel

Adjective

Might be nice to reconnect; might also be absolutely diabolical running into each other in the crisps aisle at Waitrose.

— Lauren O’Neill, Vogue, 22 Aug. 2026
What outrages Marylanders is that this diabolical plan excludes the Preakness, devaluing it and implying the Triple Crown is irrelevant, if not dead.

— Stephen J. K. Walters, Baltimore Sun, 12 Aug. 2026

Definition of diabolical

Adjective

Your husband merely identified the obvious, most vicious enemy of the people in straightforward terms.

— Andy Andersen, Vulture, 30 Aug. 2026
Democrats have little trouble understanding that the right-wing infighting over Carlson is about whether the Republican tent, which already includes racists, nativists, and vicious Islamophobes, is also big enough to include anti-Semites.

— Jonathan Chait, The Atlantic, 28 Aug. 2026

Definition of vicious

Adjective

Bryan Singer’s ingenious thriller is both a graceful callback to ’50s potboilers and a savage modernization of them.

— Declan Gallagher, Entertainment Weekly, 3 Sep. 2026
Cole, who has to maneuver his way around 20 savage crew members, each of whom will need to be killed, doesn’t waste a homicidal movement.

— Owen Gleiberman, Variety, 19 Aug. 2026

Definition of savage

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“Fiendish.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/fiendish. Accessed 10 Sep. 2026.

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Synonyms of fiendish

adjective

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