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

• alluvion
• bath
• cataract
• deluge
• flood
• flood tide
• inundation
• Niagara
• overflow
• spate
• 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

In the real world, though, the cataclysm can come in on little cat feet. —Andrew Marantz, New Yorker, 28 Apr. 2025

The effect can't be explained by lava temperatures alone, but rather a different event from the cataclysm. —Michael Franco, New Atlas, 28 Feb. 2025

When neutron stars merge, plus possibly when other stellar cataclysms (such as supernovae or exploding white dwarfs) occur, both U-235 and U-238 are produced. —Big Think, 10 Apr. 2025

Uranium, for example, is created in stellar cataclysms, with kilonova events — or colliding and merging neutron stars that don’t immediately form a black hole — doing the majority of creation for this element and its isotopes. —Big Think, 10 Apr. 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