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

Synonyms & Similar Words

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 film stars Jessica Chastain in a dual role as a mother whose daughter (Arabella Olivia Clark) is being haunted by a demonic entity.

— James Hibberd, HollywoodReporter, 8 Oct. 2026
In a world fractured by power, fear and political extremism, a group of women uncovers a demonic force operating at the highest level of society-and realizes the chaos around them may be part of a much darker design.

— Annika Pham, Variety, 6 Oct. 2026

Definition of demonic

Adjective

Now in his 25th year on television, Chuck has built a beloved media career through brutal honesty.

— Alejandro Avila OutKick, FOXNews.com, 23 Oct. 2026
Although the decrease in shot volume wasn’t quite as dramatic, Giddey went 1-for-10 from the field and scored only two points in Wednesday’s brutal beatdown by the Raptors.

— Julia Poe, Chicago Tribune, 22 Oct. 2026

Definition of brutal

Adjective

In response to legislation to end the cruelty once and for all, the Daily News once again trotted out its old and tired defense of this cruel, deadly and outdated industry.

— Voice of the People, New York Daily News, 18 Oct. 2026
Policing cringe is the cruelest métier of the internet—the origin of harassment campaigns and platforming of contempt.

— Eugenie Brinkema, ARTnews.com, 17 Oct. 2026

Definition of cruel

Adjective

Numerous treatise writers began to insist that anyone who doubts the diabolical empowerment of women-as-witches is self-deluded and dangerous.

— Literary Hub, Literary Hub, 14 Oct. 2026
Almost as soon as Jackie enters her flat there, she is accosted by gunmen, narrowly escaping before learning the diabolical and psychopathic mercenaries, The Seven Demons, have been tasked with ending her life.

— Aramide Tinubu, Variety, 2 Oct. 2026

Definition of diabolical

Adjective

So too, the possibility of Rollerball-style carnage carnivals where robots compete in vicious cage matches until only one android is still moving.

— Rick Burton, Sportico.com, 19 Oct. 2026
Cash reserves totaling $ 7,450,869 are being used to eviscerate his opponent with a vicious barrage of ad hominem assaults, thus giving him a 61 to 1 spending edge.

— Arkansas Online, Arkansas Online, 16 Oct. 2026

Definition of vicious

Adjective

The malicious system component silently installs apps that look like weather tools, app lockers and other everyday utilities.

— Kurt Knutsson, FOXNews.com, 23 Oct. 2026
The Federal Bureau of Investigation also warned that malicious actors could exploit the vulnerabilities to execute code remotely, putting sensitive data and networks at risk.

— Jenny Lee, CNBC, 22 Oct. 2026

Definition of malicious

Adjective

Onscreen, this ethnic conflict allowed Ken-san and other kimonoed gangsters to be presented as pure, sincere, patriotic heroes fighting for traditional Japanese values against savage aliens as well as local, gun-toting yakuza.

— Ian Buruma, New Yorker, 12 Oct. 2026
The Indian pilot who fought off a savage attack by his copilot and helped prevent an apparent hijack of a Flydubai plane heading to Israel with more than 170 people on board is being hailed as a hero.

— Rhea Mogul, CNN Money, 1 Oct. 2026

Definition of savage

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“Fiendish.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/fiendish. Accessed 26 Oct. 2026.

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Synonyms of fiendish

adjective

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