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 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 Miller works with him to refine the routes, placing checkpoints that are both fair and fiendish. — New Atlas, 1 Nov. 2025 See All Example Sentences for fiendish

Recent Examples of Synonyms for fiendish

Adjective

By the time Irv and Kath met, the Oberbach Corporation was ankle-deep in concrete, middle-manning the cheap Chinese labor the city needed to build its demonic underground highway along the river.

— Literary Hub, Literary Hub, 11 Aug. 2026
Pane and McKay revealed that British actor Simon Pegg will voice the Balrog, a giant demonic monster who helps Sauron forge the One Ring.

— Laura Sirikul, Forbes.com, 27 July 2026

Definition of demonic

Adjective

What follows is a brutal fight for survival against aggressive, hungry, and carnivorous dinosaurs who quickly turn the community's previously idyllic streets into their own personal feeding ground.

— Megan McCluskey, Time, 14 Aug. 2026
The company's earnings should also benefit from a better freight cycle, which has shown signs of improvement after a brutal multiyear recession that began in 2022.

— Jeff Marks, CNBC, 14 Aug. 2026

Definition of brutal

Adjective

When his girlfriend, Nicki (Debbie Harry), disappears at an audition for the show, he is drawn even deeper into its sinister world.

— Declan Gallagher, Entertainment Weekly, 7 Aug. 2026
Jordan Roth plays Bentley’s somewhat sinister, sometimes helpful right hand kitted out post-glam Bowie style.

— Robert Lloyd, Los Angeles Times, 5 Aug. 2026

Definition of sinister

Adjective

Oleksa watches them from the other end of the camera feed, in the middle of a gnarly interrogation with Kyle and Cruz — the latter silently watching Oleksa go through a cruel facsimile of her own violent recruitment crucible in the first season.

— Andy Andersen, Vulture, 16 Aug. 2026
Murder charge 'cruel and unusual,' advocate says Of cases where a child was unknowingly left in a car, about 41% do not lead to criminal charges against caregivers, Rollins said.

— Jeanine Santucci, USA Today, 15 Aug. 2026

Definition of cruel

Adjective

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
The late Lance Reddick is a delight in one of his final roles, as their diabolical CEO.

— Judy Berman, Time, 11 Aug. 2026

Definition of diabolical

Adjective

This will likely not be the last time US courts see the malicious tactic, as AI tools become more commonplace in court systems.

— Ashley Belanger, ArsTechnica, 14 Aug. 2026
After all, an agent could accept a URL and download a malicious package without its human user even knowing.

— David Berreby, IEEE Spectrum, 13 Aug. 2026

Definition of malicious

Adjective

The savage battles of Iwo Jima and Okinawa had already demonstrated the ferocity with which Japanese forces would defend their homeland.

— James M. Scott, Time, 10 Aug. 2026
The lifestyle mogul made a savage comment about Meghan Markle in a cover story for PEOPLE on Wednesday, calling out her Netflix show, With Love, Meghan.

— Leigh Blickley, Entertainment Weekly, 6 Aug. 2026

Definition of savage

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“Fiendish.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/fiendish. Accessed 18 Aug. 2026.

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Synonyms of fiendish

adjective

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