cataclysmal

adjective

variants or cataclysmic
1
as in disastrous
bringing about ruin or misfortune a cataclysmal decision to plunge the nation into war

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2
as in devastating
causing or tending to cause destruction a cataclysmal landslide that virtually wiped out the village

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3
as in turbulent
marked by sudden or violent disturbance the French Revolution was one of the great cataclysmal events in modern history

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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 cataclysmal This gave more insight into what happened in the immediate and long-term aftermath of this cataclysmic event. — Elizabeth Rayne, ArsTechnica, 30 Sep. 2026 The simulations showed that moons smaller than 620 miles across were unlikely to retain an ocean after a cataclysmic impact. — Keith Cooper, Space.com, 27 Sep. 2026 Several of the researchers who spoke to NBC News said that humans could leverage AI systems to inflict cataclysmic damage well before recursive self-improvement materializes. — Jared Perlo, NBC news, 19 Sep. 2026 The diagnosis is cataclysmic, bringing Sandra’s career to an abrupt close. — Natalia Winkelman, Variety, 16 Sep. 2026 In 2026, how reasonable are fears that AI, either by escaping human control or through misuse by unscrupulous people, could cause a cataclysmic event or the downfall of civilization? — ABC News, 14 Sep. 2026 Rising global temperatures have made high-mountain areas across the globe more unstable—and the risks of cataclysmic events have increased. — Jackie Flynn Mogensen, Scientific American, 2 Sep. 2026 The mountains above had unleashed a cataclysmic, deluge that swept 62 miles (100 km) downstream, killing hundreds and burying entire communities in the worst natural disaster to hit Nepal in years. — Ross Adkin, CNN Money, 30 Aug. 2026 The effect of the wealth consolidation carefully, and secretly, orchestrated by the SEC and Big 10 has been not catastrophic to those not in these respective leagues, but at least cataclysmic. — Fort Worth Star-Telegram, 26 Aug. 2026
Recent Examples of Synonyms for cataclysmal
  1. disastrous
  2. devastating
  3. turbulent
  4. fatal
  5. destructive
  6. unfortunate
  7. catastrophic
Adjective
  • The designer had felt the atmosphere shift after her disastrous outdoor cruise collection in Marseille in May 2024, which was marred by a mini-storm.
    — Joelle Diderich, Footwear News, 3 Oct. 2026
  • European leaders and oil executives at the time said that such a ban would be disastrous for long-term oil flow.
    — Rebecca Schneid, Time, 3 Oct. 2026
Definition of disastrous
Adjective
  • Families confronting a devastating diagnosis may already be frightened, grieving and overwhelmed.
    — Arkansas Online, Arkansas Online, 3 Oct. 2026
  • Nepal is still recovering from devastating flooding in August that swept away several villages, leaving more than 1,400 people dead and nearly 6,000 missing.
    — ABC News, ABC News, 2 Oct. 2026
Definition of devastating
Adjective
  • The vessel will navigate south through the narrow Strait of Malacca, round the turbulent waters of the Cape of Good Hope, and traverse the open expanse of the South Atlantic before dropping anchor off Bahia’s coast.
    — Mrigakshi Dixit, Interesting Engineering, 29 Sep. 2026
  • The unusual situation follows a turbulent stretch for CMS leadership.
    — Nora O'Neill, Charlotte Observer, 28 Sep. 2026
Definition of turbulent
Adjective
  • Independent media outlets like Baikal People reported that the fatal chain of events began on September 25.
    — Mrigakshi Dixit, Interesting Engineering, 5 Oct. 2026
  • Chicago Alderman Michelle Harris said at Sunday's community vigil that the suspect had allegedly gotten into an altercation with staff at a wireless store in the Chatham neighborhood just before the fatal stabbing, WLS reported.
    — ABC News, ABC News, 5 Oct. 2026
Definition of fatal
Adjective
  • Recent warnings about the potential destructive power of AI are understating the severity of the situation.
    — Geoffrey Irving, Time, 3 Oct. 2026
  • Desperate to change, Tonya turns to her estranged mother, Wanda (Miller), who offers little concern and instead accuses her of repeating the same destructive patterns that shaped her own childhood.
    — Andreas Wiseman, Deadline, 2 Oct. 2026
Definition of destructive
Adjective
  • These unfortunate souls were supposed to stay in their birthplace, hoping church charity would sustain them.
    — Literary Hub, Literary Hub, 28 Sep. 2026
  • Artistic but flighty, Deborah ends up at her parents’ alma mater when an unfortunate incident gets her NYU Tisch School of the Arts acceptance rescinded.
    — Aramide Tinubu, Variety, 24 Sep. 2026
Definition of unfortunate
Adjective
  • Refining these predictive models will also improve safety for reentry vehicles and high-speed aircraft, ultimately minimizing or eliminating catastrophic water damage.
    — Mrigakshi Dixit, Interesting Engineering, 29 Sep. 2026
  • If that wasn’t bad enough, the dead satellites would start crashing into things, creating cascades of high-speed debris that could destroy most remaining satellites in a catastrophic domino effect called Kessler syndrome.
    — Mary Randolph, Scientific American, 29 Sep. 2026
Definition of catastrophic

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Cite this Entry

“Cataclysmal.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/cataclysmal. Accessed 6 Oct. 2026.

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