n. pl. ca·su·al·ties
a. One who is injured or killed in an accident: a train wreck with many casualties.
b. One who is injured, killed, captured, or missing in action through engagement with an enemy: Battlefield casualties were high.
2. One that is harmed or eliminated as a result of an action or circumstance: The corner grocery was a casualty of the expanding supermarkets.
3. An accident, especially one involving serious injury or loss of life.
[Middle English casuelte, chance, accident, from Old French, from Medieval Latin cāsuālitās, from Latin cāsuālis, fortuitous; see CASUAL.]
Usage Note: In military usage, a casualty is a serviceperson who has been killed, injured, captured, or in some other way rendered unable to serve. When used in nonmilitary situations, such as newspaper reports about accidents, the word casualty is usually used to mean a person who is either killed or injured. Sometimes, however, people use casualties to refer only to individuals who have died, not to those who have been injured. This usage is often considered an error. In our 2013 survey, 60 percent of the Usage Panel disapproved of a sentence where casualties was used to mean "fatalities" only: Officials have reported 21 casualties from yesterday's earthquake. In addition to those fatalities, 79 people were seriously injured.
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2016 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
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