fiendish

adjective

ˈfēn-dish How to pronounce fiendish (audio)
Definition of fiendishnext
1
as in demonic
of, relating to, or worthy of an evil spirit a fiendish delight in playing cruel tricks

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Antonyms & Near Antonyms
2
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 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
  1. demonic
  2. brutal
  3. sinister
  4. cruel
  5. diabolical
  6. vicious
  7. malicious
  8. savage
Adjective
  • 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
  • Higuchi was already at home in this rubbery soundworld, but his determination to work out his own feelings in this already frenzied context pushes his music past the cartoonish and into the truly demonic.
    — Daniel Bromfield, Pitchfork, 27 July 2026
Definition of demonic
Adjective
  • His brutal murder in Culiacán, the capital of the northwestern Mexican state of Sinaloa, happened in just a few seconds on Tuesday in front of an audience of thousands of social media users watching his TikTok stream.
    — Rey Rodríguez, CNN Money, 8 Aug. 2026
  • Deliberate exposure is a brutal test — in this trial, 81% of the placebo group got sick, experiencing diarrhea and fever in some cases before receiving antibiotics.
    — Joseph Kim, NPR, 7 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
  • Impermanence turns out to be the cruelest fact and the most merciful one at once.
    — Dr. Lucy McBride, Time, 8 Aug. 2026
  • His central characters can be nasty, disgusting, violent, hysterically cruel, and passionately consumed.
    — CT Jones, Rolling Stone, 8 Aug. 2026
Definition of cruel
Adjective
  • The actress also had a memorable guest turn on The Vampire Diaries and reunited with Ben McKenzie for a diabolical three-episode run on Gotham.
    — Kevin Jacobsen, Entertainment Weekly, 5 Aug. 2026
  • Super-secret spec-ops military squads facing off against the next diabolical terrorist threat.
    — Erik Kain, Forbes.com, 31 July 2026
Definition of diabolical
Adjective
  • And on the other side of the ball, this defense has a chance to be downright vicious.
    — Dieter Kurtenbach, Mercury News, 12 Aug. 2026
  • Heidegger, the philosopher of authenticity and independent thought, had become one of them, surrendering to vicious political cant.
    — David Denby, New Yorker, 10 Aug. 2026
Definition of vicious
Adjective
  • The company wants advanced cybersecurity models to strengthen digital defenses by helping security teams identify and fix vulnerabilities before malicious actors can exploit them.
    — Aamir Khollam, Interesting Engineering, 7 Aug. 2026
  • Their job is to hack devices and patch exploits before malicious actors do.
    — Justyn Newman, PC Magazine, 7 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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Cite this Entry

“Fiendish.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/fiendish. Accessed 14 Aug. 2026.

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Nglish: Translation of fiendish for Spanish Speakers

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