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

Synonyms & Similar Words

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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
  • 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
  • The Braves have Drake Baldwin and Sean Murphy atop their catching depth chart, but a brutal injury setback involving veteran backstop Sandy Leon has now forced the organization to seek out another experienced option.
    — Peter Chawaga, Forbes.com, 21 Aug. 2026
  • Micron, as well as South Korea's SK Hynix and Samsung Electronics — the world's three major DRAM producers — had competed largely on price, contributing to the brutal boom-and-bust cycles that have long characterized the industry.
    — Alexa LoMonaco, CNBC, 21 Aug. 2026
Definition of brutal
Adjective
  • In the more familiar galaxy far, far away, their friends Hera Syndulla, Ezra Bridger, Zeb Orrelios and Chopper must face the powerful Grand Admiral Thrawn and his sinister allies, who seek to plunge the fledgling New Republic into war.
    — Angeline Jane Bernabe, ABC News, 15 Aug. 2026
  • The clip released last night shows this is a more complex, sinister strategist than Josh Brolin’s crash-bang-boom baddie Thanos from the previous Avengers pics.
    — Anthony D'Alessandro, Deadline, 15 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
  • But Roy’s story of Annie (Arjun Raina), a New Delhi architecture student caught in a vicious cycle of failing and repeating his studies, gradually reveals itself as a sharp and poignant portrayal of youth, deftly poised between hope and cynicism.
    — Jill Goldsmith, Deadline, 18 Aug. 2026
  • Lawsuits, bureaucratic battles, boisterously divisive council arguments and vicious social media debates have been part of Bloomfield life for years, and intensified during Danielle Wong’s contentious time as mayor.
    — Don Stacom, Hartford Courant, 18 Aug. 2026
Definition of vicious
Adjective
  • Use strong security software Good security software can help protect you from malicious links, phishing attempts and other online threats that may try to steal your information.
    — Kurt Knutsson, FOXNews.com, 21 Aug. 2026
  • Many phones silently join familiar-looking networks without user confirmation, a behavior that attackers exploit through malicious wireless access points that mimic trusted hotspots.
    — Expert Panel®, Forbes.com, 20 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 23 Aug. 2026.

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Nglish: Translation of fiendish for Spanish Speakers

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