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
  • Intrigued by this odd, demonic figure, Tubbs started a conversation.
    — Literary Hub, Literary Hub, 10 July 2026
  • After Will’s funeral, Alice retreats to her in-laws’ remote, dilapidated house, where, through the Necronomicon, a demonic spirit is unleashed and begins to turn the family members into Deadites.
    — Tim Lammers, Forbes.com, 8 July 2026
Definition of demonic
Adjective
  • But for one more summer, there’s Wednesday night hockey in the suburbs, the tickets are cheap, the autographs are free, and the arena is air conditioned in the midst of a brutal heat wave.
    — Jess Myers, Twin Cities, 17 July 2026
  • Shop Cooling Summer Dresses at REI This summer has proven to be particularly brutal, with heat waves engulfing a massive portion of the country.
    — Tanya Sharma, PEOPLE, 17 July 2026
Definition of brutal
Adjective
  • The concept survived the hedonistic ’80s, the grimy ’90s, and the low-rise aughts only to reemerge in the social media age with a new name and a more sinister purpose.
    — Hillary Busis, Vanity Fair, 14 July 2026
  • Fate, or something more sinister, will set them on an unexpected road trip, with devastating consequences.
    — John Hopewell, Variety, 14 July 2026
Definition of sinister
Adjective
  • But in one of the cruelest ironies in rock history, Berry suffered a devastating car crash not far from the actual Dead Man’s Curve in Los Angeles on April 12, 1966.
    — Andy Greene, Rolling Stone, 19 July 2026
  • In the face of climate change, such woo woo aphorisms seem ridiculous, naive, and cruel.
    — Josh Fox, IndieWire, 17 July 2026
Definition of cruel
Adjective
  • When Ahab first speaks to the crew about Moby Dick, his diabolical charisma soon infects the men who, apart from Starbuck, enthusiastically join him in his monomaniacal crusade.
    — Literary Hub, Literary Hub, 6 July 2026
  • From perhaps the most diabolical spot on the entire course.
    — Brendan Quinn, New York Times, 20 June 2026
Definition of diabolical
Adjective
  • Yet falling behind on payments could result in a vicious cycle of debt, experts say.
    — Stephanie Dhue,Sharon Epperson, CNBC, 14 July 2026
  • As Earth warms, more permafrost melts, releasing even more methane and creating a vicious cycle.
    — Vahe Peroomian, The Conversation, 13 July 2026
Definition of vicious
Adjective
  • Ransomware is a type of malicious software that restricts access to computer files, systems, or networks, according to the FBI.
    — Melina Khan, USA Today, 17 July 2026
  • Rodriguez pleaded guilty to damaging property occupied by a foreign government, explosive materials—malicious damage to federal property, and receipt or possession of an unregistered firearm.
    — David J. Neal, Miami Herald, 16 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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Cite this Entry

“Fiendish.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/fiendish. Accessed 20 Jul. 2026.

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Nglish: Translation of fiendish for Spanish Speakers

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