diabolical

adjective

ˌdī-ə-ˈbä-li-kəl How to pronounce diabolical (audio)
variants or diabolic
Definition of diabolicalnext
as in demonic
of, relating to, or worthy of an evil spirit the police quickly mobilized to track down the diabolical criminals before they struck again

Synonyms & Similar Words

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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 diabolical 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 The late Lance Reddick is a delight in one of his final roles, as their diabolical CEO. — Judy Berman, Time, 11 Aug. 2026 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 See All Example Sentences for diabolical
Recent Examples of Synonyms for diabolical
  1. demonic
  2. sinister
  3. malicious
Adjective
  • Short enough to read in a single sitting, Sara Gran’s chilling story of an architect succumbing to demonic possession will leave readers stunned and unsettled.
    — David Faris, TheWeek, 23 Oct. 2026
  • In 1999, demonic rollerblading triplets armed with hockey sticks laid cross-checks on the likes of Bud Cort and Chris Rock in Kevin Smith’s Dogma.
    — Brian Davids, HollywoodReporter, 21 Oct. 2026
Definition of demonic
Adjective
  • Feathers McGraw, the sinister penguin villain from the Wallace & Gromit films, also makes a Hitchcockian cameo.
    — Scott Roxborough, HollywoodReporter, 22 Oct. 2026
  • Other examples are more sinister—for instance, the far-right takeover of Croatian Wikipedia, or efforts by corporations to launder their images.
    — Julian Lucas, New Yorker, 21 Oct. 2026
Definition of sinister
Adjective
  • The malicious system component silently installs apps that look like weather tools, app lockers and other everyday utilities.
    — Kurt Knutsson, FOXNews.com, 23 Oct. 2026
  • The Federal Bureau of Investigation also warned that malicious actors could exploit the vulnerabilities to execute code remotely, putting sensitive data and networks at risk.
    — Jenny Lee, CNBC, 22 Oct. 2026
Definition of malicious

Browse Nearby Words

diableries
diabolical
diabolically
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Cite this Entry

“Diabolical.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/diabolical. Accessed 30 Oct. 2026.

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