1,400 new words in our dictionary! — Parasocial, glow-up, promposal & more
1,400 new words in our dictionary! — More

cataclysmal

adjective

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

Synonyms & Similar Words

Relevance

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

Synonyms & Similar Words

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

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 cataclysmal 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 The pound’s loss of reserve currency status wasn’t a cataclysmic event but a slow decline over decades. — Philipp Carlsson-Szlezak, Fortune, 17 July 2026 Despite ample warnings from the National Weather Service that potentially cataclysmic winds were bound for the city in the heart of its fire season, Bass headed to Ghana for a diplomatic event and was in Africa as the city burned. — John Scott Lewinski, The Washington Examiner, 11 July 2026
Recent Examples of Synonyms for cataclysmal
  1. disastrous
  2. devastating
  3. turbulent
  4. fatal
  5. destructive
  6. unfortunate
  7. catastrophic
Adjective
  • The disastrous late-August flash flooding near Phantom Ranch struck below the burn scar left by that blaze, the National Weather Service said.
    — Chris Boyette, CNN Money, 3 Sep. 2026
  • The bill for the disastrous Leonard era now includes Shai Gilgeous-Alexander — the reigning, two-time MVP — 10 first-round picks and two additional pick swaps.
    — Jason Lloyd, New York Times, 3 Sep. 2026
Definition of disastrous
Adjective
  • Here are a few of the fronts on which that undeclared war is being fought, with devastating consequences for the next generation of Americans.
    — David Wippman, Washington Post, 11 Sep. 2026
  • Twenty-five years after the devastating terror attacks, the retired Bountiful, Utah, resident still carries the memories of that day ​— not only the fear and uncertainty, but also the camaraderie and grief shared by those around him.
    — Kaanita Iyer, CNN Money, 11 Sep. 2026
Definition of devastating
Adjective
  • His re-election came on the back of a turbulent few years, ones where Barca’s finances were as much a story as their football.
    — Chris Weatherspoon, New York Times, 11 Sep. 2026
  • The new play follows the fortunes of a wealthy but troubled clan through a turbulent period in Nigeria’s recent history.
    — Zac Ntim, Deadline, 10 Sep. 2026
Definition of turbulent
Adjective
  • That is until his young niece and nephew are kidnapped at a birthday party following the fatal shooting of his diplomat brother and the latter’s wife (Constanza Andrade).
    — Michael Rechtshaffen, HollywoodReporter, 14 Sep. 2026
  • Boeing admitted responsibility for the fatal crashes and that its employees withheld information about the design flaw from the Federal Aviation Administration during certification.
    — Alexandra Skores, CNN Money, 14 Sep. 2026
Definition of fatal
Adjective
  • Large, destructive waves and life-threatening rip currents are forecast across many Hawaiian shorelines during the next several days.
    — Anthony Thompson, USA Today, 7 Sep. 2026
  • America’s sense of security was smashed with apocalyptic fury Tuesday when the most destructive and meticulously planned terror attack in history shattered two of the country’s most potent symbols.
    — Christopher Keating, Hartford Courant, 6 Sep. 2026
Definition of destructive
Adjective
  • That is the unfortunate part of a tenure full of expansion, media-rights billions and two transformational collective bargaining agreements.
    — Jerry Brewer, New York Times, 9 Sep. 2026
  • Moore and his allies are presenting gerrymandering as an unfortunate response to an acute political crisis, but trying to gerrymander Maryland in favor of Democrats is far from a new effort.
    — Colin Pascal, Baltimore Sun, 7 Sep. 2026
Definition of unfortunate
Adjective
  • The dependency is often invisible in normal times but could be catastrophic in a crisis.
    — Sajal Singh, Forbes.com, 8 Sep. 2026
  • Not just any bill, but this year’s biggest in the state Legislature, dealing with catastrophic wildfires, arguably the state’s most perilous problem.
    — Los Angeles Times, Los Angeles Times, 7 Sep. 2026
Definition of catastrophic

Browse Nearby Words

cataclysm
cataclysmal
cataclysms
See all Nearby Words

Cite this Entry

“Cataclysmal.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/cataclysmal. Accessed 15 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!

More from Merriam-Webster

Word of the Day

Listen to the pronunciation of quorum

See Definitions and Examples »

Popular in Grammar & Usage

See More

Merriam-Webster’s Great Big List of Words You Love to Hate

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

Why do we use apostrophes to show possession?

'A' or 'an'? What about before 'h'? An Indefinite Article Guide

Why is '-ed' sometimes pronounced at the end of a word?
See More

Popular in Wordplay

See More

9 Words That Sound Like Insults But Aren't

Back to School Vocabulary

Words from the 'Odyssey'

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

14 Phobias You Probably Haven't Heard Of
See More

Popular

See More

Merriam-Webster’s Great Big List of Words You Love to Hate

9 Words That Sound Like Insults But Aren't

Back to School Vocabulary
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
funny guinea pig in glasses reading a book
Challenging Words You Should Know Vol 2 Words to the wise
See All