casualty

noun

ca·​su·​al·​ty ˈka-zhəl-tē 

ˈkazh-wəl-,

ˈka-zhə-wəl- 

plural casualties

1

a

: a military person lost through death, wounds, injury, sickness, internment, or capture or through being missing in action

The army sustained heavy casualties.

b

: a person or thing injured, lost, or destroyed : victim

the ex-senator was a casualty of the last election

2

: serious or fatal accident : disaster

losses from fire, storm, or other casualty

—J. S. Seidman

3

archaic : chance, fortune

losses that befall them by mere casualty

—Sir Walter Raleigh

Synonyms

• victim
• fatality

Examples of casualty in a Sentence

a low number of casualties

the real casualties in the war against drugs are millions of innocent children

Recent Examples on the Web

Ostapenko claims her intent was not racist and instead a casualty of English as a second language. —Merlisa Lawrence Corbett, Forbes.com, 31 Aug. 2025

The meeting was the latest honoring of troops who suffered heavy casualties in Russia’s Kursk region that borders Ukraine, after Kim and Russian President Vladimir Putin acknowledged the deployment in April after months of silence. —CNN Money, 30 Aug. 2025

Aid organizations and global leaders warn that further restrictions could exacerbate starvation, displacement, and civilian casualties, especially as Israel prepares to evacuate hundreds of thousands of residents from Gaza City. —Amanda Castro, MSNBC Newsweek, 30 Aug. 2025

Israel confirmed the strike targeted senior Houthi officials but did not confirm all casualties. —Reuters, USA Today, 30 Aug. 2025

Word History

Etymology

see casual entry 1

First Known Use

15th century, in the meaning defined at sense 3

Kids Definition

casualty

noun

ca·​su·​al·​ty ˈkazh-əl-tē 

ˈkazh-(ə-)wəl-

plural casualties

1

: a serious or fatal accident : disaster

2

a

: a military person lost (as by death or capture) during warfare

b

: a person or thing injured, lost, or destroyed

Medical Definition

casualty

noun

ca·​su·​al·​ty ˈkazh-əl-tē, ˈkazh-(ə-)wəl- 

plural casualties

1

: a serious or fatal accident

2

: a military person lost through death, wounds, injury, sickness, internment, or capture or through being missing in action

3

a

: injury or death from accident

b

: one injured or killed (as by accident)

Legal Definition

casualty

noun

ca·​su·​al·​ty ˈka-zhəl-tē, ˈka-zhə-wəl- 

plural casualties

1

: an unfortunate occurrence

especially : a serious and often disastrous accident

conversion of property…arising from fire, storm, shipwreck, or other casualty

—Internal Revenue Code

2

: something lost, stolen, damaged, or destroyed see also casualty gain at gain, casualty loss at loss