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

Intrigued by this odd, demonic figure, Tubbs started a conversation.

— Literary Hub, Literary Hub, 10 July 2026
After Will’s funeral, Alice retreats to her in-laws’ remote, dilapidated house, where, through the Necronomicon, a demonic spirit is unleashed and begins to turn the family members into Deadites.

— Tim Lammers, Forbes.com, 8 July 2026

Definition of demonic

Adjective

San Francisco has already seen right-hander Hayden Birdsong undergo Tommy John surgery earlier this year, and losing McDonald for an extended period of time would be another brutal blow for the pitching staff.

— Justice delos Santos, Mercury News, 25 July 2026
This thing—the military—aims, at least in Harlow’s eyes, to turn boys into tools for brutal battlefield aims.

— Jasper Craven, New Yorker, 24 July 2026

Definition of brutal

Adjective

There was something so sinister about FIFA pushing the idea of diversity while bending the knee to a government working to discard the real thing.

— Olivier Lafontant, Pitchfork, 20 July 2026
Outside, the cops, led by a dry sinister officer in a long black leather coat, order him to get on the ground, face down; Sophia comes out of the house and is placed in the back of a car, staring at all this through the glass.

— Owen Gleiberman, Variety, 16 July 2026

Definition of sinister

Adjective

But in one of the cruelest ironies in rock history, Berry suffered a devastating car crash not far from the actual Dead Man’s Curve in Los Angeles on April 12, 1966.

— Andy Greene, Rolling Stone, 19 July 2026
In the face of climate change, such woo woo aphorisms seem ridiculous, naive, and cruel.

— Josh Fox, IndieWire, 17 July 2026

Definition of cruel

Adjective

When Ahab first speaks to the crew about Moby Dick, his diabolical charisma soon infects the men who, apart from Starbuck, enthusiastically join him in his monomaniacal crusade.

— Literary Hub, Literary Hub, 6 July 2026
From perhaps the most diabolical spot on the entire course.

— Brendan Quinn, New York Times, 20 June 2026

Definition of diabolical

Adjective

Harbaugh had tense standoffs with legacy defenders Ed Reed, Ray Lewis and Terrell Suggs and, during the 2012 season, held a sitdown with his players to address their vicious and personal attacks on his approach.

— Ian O'Connor, New York Times, 22 July 2026
The film also shows Maddox and her father in a vicious argument inside her car that illustrates the fracturing of their once-close bond.

— Los Angeles Times, Los Angeles Times, 22 July 2026

Definition of vicious

Adjective

On this occasion, OpenAI appears to have been transparent about its involvement in the incident and is working alongside Hugging Face to respond, but defenders need to prepare for a world where such tools are in the hands of openly malicious actors.

— Tim Keary, Forbes.com, 23 July 2026
Skubal did not say those words about the MRI and the arbitration hearing with any malicious tone.

— Cody Stavenhagen, New York Times, 22 July 2026

Definition of malicious

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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 26 Jul. 2026.

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Synonyms of fiendish

adjective

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