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

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Antonyms & Near Antonyms
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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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 cataclysmal 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 Barring a cataclysmic injury, all of this translates into an eventual Young contract extension. — Scott Fowler, Charlotte Observer, 30 July 2026 But the shockwaves of this cataclysmic blast will stretch far beyond the fifth planet. — Richard Edwards, Space.com, 23 July 2026
Recent Examples of Synonyms for cataclysmal
  1. disastrous
  2. devastating
  3. turbulent
  4. fatal
  5. destructive
  6. unfortunate
  7. catastrophic
Adjective
  • The agency might even take the opportunity to completely redesign the disastrous Ashland, Armitage and Elston Avenue intersection and save generations of Chicagoans the headache of spending 15 minutes navigating through a single stoplight.
    — Chicago Tribune, Chicago Tribune, 19 Sep. 2026
  • Where his focus has been following the Dolphins’ special team unit’s disastrous performance in Miami’s 27-13 loss to the Las Vegas Raiders is patching the leaks that led to three massive returns to the Raiders and a missing a field-goal attempt.
    — Omar Kelly, Miami Herald, 18 Sep. 2026
Definition of disastrous
Adjective
  • These are the glimmers of something in the fringes that keep The Cherry Orchard, even in our age of jonesing to burn it all down, so miraculously delicate and devastating.
    — Sara Holdren, Vulture, 18 Sep. 2026
  • The survival thriller, directed by David Ayer, follows a Special Forces officer and his combat dog who, after a devastating plane crash, get stranded deep in the Alaskan wilderness.
    — Angelique Jackson, Variety, 18 Sep. 2026
Definition of devastating
Adjective
  • The oversight hearing underscored Patel’s turbulent tenure, from shouting matches with lawmakers and blended leisure travel to allegations of excessive drinking that spurred calls for his removal and a massive defamation suit.
    — Eric Tucker, Los Angeles Times, 15 Sep. 2026
  • The two lawsuits come after a turbulent week for Hoskins, a Republican who became a key player in a dizzying series of legal battles and court decisions over the state’s congressional map.
    — Kacen Bayless, Kansas City Star, 15 Sep. 2026
Definition of turbulent
Adjective
  • After 16 months of radiation and chemotherapy, a September 2025 scan showed the cancer had spread to his spinal cord, a condition called leptomeningeal disease that usually proves fatal within a few months.
    — Arthur Allen, CBS News, 21 Sep. 2026
  • None of the 10 students riding to Wyandotte High School on Monday morning were injured when gunfire struck their school bus during a fatal dispute.
    — Eleanor Nash, Kansas City Star, 21 Sep. 2026
Definition of fatal
Adjective
  • The project was on the side of a scrubby hill that looked nothing like the steep timber and chaparral where California’s destructive fires burn and the insurance market has fled.
    — Paige St. John, Los Angeles Times, 20 Sep. 2026
  • The violence was easier to process then as a negative act, something destructive.
    — Bilge Ebiri, Vulture, 18 Sep. 2026
Definition of destructive
Adjective
  • One of these evils had the mass murder of civilians as its intended goal; the other claims that its victims are unfortunate accidents.
    — Literary Hub, Literary Hub, 18 Sep. 2026
  • But those who get too close risk far more than a soaking, as Niagara is a graveyard for the reckless, the unfortunate and the desperate.
    — Carly Tagen-Dye, PEOPLE, 18 Sep. 2026
Definition of unfortunate
Adjective
  • There were also calls for Congressional oversight hearings on AI’s catastrophic risks.
    — Jeremy Kahn, Fortune, 15 Sep. 2026
  • Chinese Foreign Ministry spokesperson Guo Jiakun urged Washington to stop expanding its military footprint off the planet, warning against a catastrophic space arms race.
    — Mrigakshi Dixit, Interesting Engineering, 15 Sep. 2026
Definition of catastrophic

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cataclysm
cataclysmal
cataclysms
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Cite this Entry

“Cataclysmal.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/cataclysmal. Accessed 22 Sep. 2026.

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