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 Devil’s portrait is included as an acknowledgment of demonic assistance.

— Laura Payne, Encyclopedia Britannica, 30 Oct. 2026
Blaze/Ghost Rider did not exactly have a signature villain but did have a coterie of demonic antagonists.

— Aaron Couch, HollywoodReporter, 27 Oct. 2026

Definition of demonic

Adjective

This version, though, is brutal, his voice acerbic and his guitar serrated.

— Grayson Haver Currin, Pitchfork, 7 Nov. 2026
And through eight games this season, those two words have defined the majority of the third-year wing’s experience on the court for the Chicago Bulls, who are 1-7 after a brutal trio of road losses in the last week.

— Julia Poe, Chicago Tribune, 6 Nov. 2026

Definition of brutal

Adjective

The festival favorite horror film, which was acquired by IFC Films and Shudder, follows a dog’s mission to protect his sickly owner from a sinister supernatural force.

— Jack Dunn, Variety, 6 Nov. 2026
Ganondorf is the ultimate example of this, with his visage keeping its cartoonishly sinister sharp angles and unnaturally green pallor.

— Will Greenwald, PC Magazine, 5 Nov. 2026

Definition of sinister

Adjective

Newsom and other opponents of capital punishment have long argued that the process is costly, cruel and discriminatory, with death sentences disproportionately handed down to defendants of color.

— Sonja Sharp, Los Angeles Times, 5 Nov. 2026
In a cruel twist of fate, the back half of the trailer shows Geoff being affected by severe confusion, sitting outside his house in the cold.

— Jason P. Frank, Vulture, 5 Nov. 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

For the moment, Trump’s vicious bigotry has alienated most independent voters and even some Republicans.

— David Yassky, New York Daily News, 2 Nov. 2026
Outside observers described his vicious consolidation of power as an attempt to compensate for his youth, his limited political experience, and his complete lack of a military background.

— Jieun Baek, Foreign Affairs, 30 Oct. 2026

Definition of vicious

Adjective

Authorities have described the more than two dozen threats as malicious hoaxes, and no actual attacks have been carried out.

— Jenni Reid, CNBC, 7 Nov. 2026
Iran has been linked to at least one incident in Israel earlier in the spring, though that breach involved a lot more sophistication and malicious activity.

— Jenna McLaughlin, NPR, 6 Nov. 2026

Definition of malicious

Adjective

Reducing Gulliver’s Travels to only a topsy-turvy tale of humans both tiny and massive is to ignore the savage intellect that penned its words.

— Literary Hub, Literary Hub, 28 Oct. 2026
In ancient, supposedly more savage times, public killings were common.

— Dr. Michael Good, Hartford Courant, 22 Oct. 2026

Definition of savage

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

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Synonyms of fiendish

adjective

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