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
  • 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
  • And, as the Punisher, Frank is known to enact particularly brutal, bloody vengeance.
    — Angelique Jackson, Variety, 31 July 2026
  • After opening the season on the big-league roster and then suffering a demotion after a brutal debut, Phillies pitcher Andrew Painter could be poised to make a stunning return to the mound against the Orioles.
    — Peter Chawaga, Forbes.com, 31 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
  • Who could be so cruel as to cut off their family from the family plan?
    — Elisabeth Buchwald, CNN Money, 1 Aug. 2026
  • Influencer culture didn’t exist yet, but some designers were cruel and catty, even without the current omnipresent evil of social media.
    — Roxana Hadadi, Vulture, 31 July 2026
Definition of cruel
Adjective
  • Super-secret spec-ops military squads facing off against the next diabolical terrorist threat.
    — Erik Kain, Forbes.com, 31 July 2026
  • Pinnock, in particular, is at his best here, showcasing a diabolical cruelty and terrifying manipulation, elevating the story and the show to a different level.
    — Aramide Tinubu, Variety, 31 July 2026
Definition of diabolical
Adjective
  • The drastic measures Alice takes to end this vicious cycle naturally bring her closer to Catherine’s school of violent retribution.
    — Alison Herman, Variety, 27 July 2026
  • Despite the powerful action and vicious fight scenes the franchise is known for, Laufey is still shaping up as a bit of a love story.
    — Brian Mazique, Forbes.com, 25 July 2026
Definition of vicious
Adjective
  • These errors can cause crashes or enable attackers to exploit memory vulnerabilities, risking data corruption or executing malicious code.
    — Davey Winder, Forbes.com, 31 July 2026
  • Elijah Bieniemy, who is 27 and is a graduate of Olathe Northwest High School, has been charged with malicious wounding, use of a firearm during the commission of a felony and discharge of a firearm inside of a dwelling.
    — Pete Grathoff, Kansas City Star, 31 July 2026
Definition of malicious
Adjective
  • The Yellow Death has disfigured the population, and soldiers in white-and-red tunics serve the savage Duke of Tviot.
    — Dan Piepenbring, Harpers Magazine, 30 June 2026
  • Josefowicz, in her decathlon of a performance, brought Ligeti’s savage discontinuities to the surface.
    — Alex Ross, New Yorker, 29 June 2026
Definition of savage

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fiendish
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Cite this Entry

“Fiendish.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/fiendish. Accessed 4 Aug. 2026.

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Nglish: Translation of fiendish for Spanish Speakers

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