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

Relevance

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
  • But cultural myths and urban legends have also stereotyped them into Halloween mascots, demonic beings and carriers of diseases.
    — Shi En Kim, AZCentral.com, 28 Aug. 2026
  • Wolf succumbs to Shura, a demonic force in the game’s mythology that possesses those who give in to bloodlust.
    — Aman Kumar, Encyclopedia Britannica, 27 Aug. 2026
Definition of demonic
Adjective
  • Within a span of four months in Fort Worth last year, Watkins and Snellings were killed in similarly brutal attacks in the Near Southside and Historic Southside sections of the city.
    — Emerson Clarridge, Fort Worth Star-Telegram, 28 Aug. 2026
  • Even so, when investor confidence broke in 1997, the adjustment was swift and brutal.
    — MICHAEL PETTIS, Foreign Affairs, 28 Aug. 2026
Definition of brutal
Adjective
  • But now Disney has shared more of what’s coming to the sinister territory just beyond the spires of the park’s Wildest Ride in the Wilderness.
    — Megan duBois, Southern Living, 17 Aug. 2026
  • 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
Definition of sinister
Adjective
  • Having Sheridan actually be a cruel person was one of the key audience expectations the writer-director hoped to flip in the pursuit of laughs.
    — William Earl, Variety, 28 Aug. 2026
  • But Triage does have a moment in which an ember of the old cruel optimism flickers.
    — Charles Finch, The Atlantic, 28 Aug. 2026
Definition of cruel
Adjective
  • Might be nice to reconnect; might also be absolutely diabolical running into each other in the crisps aisle at Waitrose.
    — Lauren O’Neill, Vogue, 22 Aug. 2026
  • 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
Definition of diabolical
Adjective
  • Detectives charged him with murder, manslaughter and criminal possession of a weapon for the vicious attack that killed his mother, 57-year-old Josefa Soto de Guzman, on Friday.
    — Colin Mixson, New York Daily News, 26 Aug. 2026
  • Pace, skill, a vicious shot, the ability to make opposition defenders look like fools.
    — James Horncastle, New York Times, 26 Aug. 2026
Definition of vicious
Adjective
  • That leaves a short window during which malicious activity can contaminate the prediction machinery again.
    — Atharva Gosavi, Interesting Engineering, 28 Aug. 2026
  • An attacker can then register the site and plant malicious instructions on it.
    — Dan Goodin, ArsTechnica, 27 Aug. 2026
Definition of malicious
Adjective
  • Cole, who has to maneuver his way around 20 savage crew members, each of whom will need to be killed, doesn’t waste a homicidal movement.
    — Owen Gleiberman, Variety, 19 Aug. 2026
  • 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
Definition of savage

Browse Nearby Words

fiend
fiendish
fiendishly
See all Nearby Words

Cite this Entry

“Fiendish.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/fiendish. Accessed 1 Sep. 2026.

Copy Citation
Last Updated: - Updated example sentences
Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!

Popular in Grammar & Usage

See More

A Who’s Who Regarding ‘Who’s’ and ‘Whose’

Is it 'nerve-racking' or 'nerve-wracking'?

What's the difference between 'fascism' and 'socialism'?

Why does English have so many silent letters?

7 Pairs of Commonly Confused Words
See More

Popular in Wordplay

See More

Ye Olde Nincompoop: Old-Fashioned Words for 'Stupid'

14 Phobias You Probably Haven't Heard Of

Even More Words That Sound Like Insults But Aren't

Even More Bird Names that Sound Like Insults (and Sometimes Are)

12 Lovely and Unusual Words for the Natural World
See More

Popular

See More

A Who’s Who Regarding ‘Who’s’ and ‘Whose’

Ye Olde Nincompoop: Old-Fashioned Words for 'Stupid'

14 Phobias You Probably Haven't Heard Of
See More

Games & Quizzes

See All
Play Quordle: Guess all four words in a limited number of tries. Each of your guesses must be a real 5-letter word.
Quordle Can you solve 4 words at once?
Play Blossom: Solve today's spelling word game by finding as many words as you can using just 7 letters. Longer words score more points.
Blossom Pick the best words!
Play Missing Letter: a crossword with a twist. Each of the 25 puzzle words start with a different letter of the alphabet. Which letter is missing?
The Missing Letter A daily crossword with a twist
skateboard-dog-hat
Wordmaxxing Slang Quiz Give your vocabulary a glow up by getting sendy w...
See All