cataclysm

noun

cat·​a·​clysm ˈka-tə-ˌkli-zəm 

1

: flood, deluge

2

: catastrophe sense 3a

3

: a momentous and violent event marked by overwhelming upheaval and demolition

broadly : an event that brings great changes

an international economic cataclysm

cataclysmal

ˌka-tə-ˈkliz-məl 

adjective

or cataclysmic

ˌka-tə-ˈkliz-mik 

cataclysmically

ˌka-tə-ˈkliz-mi-k(ə-)lē 

adverb

Synonyms of cataclysm

• flood
• torrent

Examples of cataclysm in a Sentence

floods, earthquakes, and other cataclysms

The country barely survived the cataclysm of war.

The revolution could result in worldwide cataclysm.

Recent Examples on the Web

There were armed conflicts in the DRC during Mobutu's reign, but nothing on the scale of the cataclysm that erupted after he was ousted. —Emmet Livingstone, NPR, 23 Nov. 2025

At the universe's grandest scales, galaxy clusters collide in slow-motion cataclysms, leaving behind immense, ghostly arcs — vast ribbons of diffuse radio emissions that can stretch across millions of light-years. —Sharmila Kuthunur, Space.com, 21 Nov. 2025

Every year, come rain or shine or strike or global cataclysm, Slow Horses delivers a new season. —Daniel Fienberg, HollywoodReporter, 29 Oct. 2025

The travelers that interested her were not those seeking plain or ordinary pleasures but those chasing a profound personal cataclysm. —Nicole Flattery, Harpers Magazine, 19 Sep. 2025

Word History

Etymology

French cataclysme, from Latin cataclysmos, from Greek kataklysmos, from kataklyzein to inundate, from kata- + klyzein to wash — more at clyster

First Known Use

1599, in the meaning defined at sense 1

Rhymes for cataclysm

• alyssum
• aneurysm

Kids Definition

cataclysm

noun

cat·​a·​clysm ˈkat-ə-ˌkliz-əm 

1

: a great flood

2

: a violent and destructive natural event (as an earthquake)

3

: a violent social or political change

cataclysmal

ˌkat-ə-ˈkliz-məl 

adjective

or cataclysmic

-mik