noun, plural cas·u·al·ties.
- Military.
- a member of the armed forces lost to service through death, wounds, sickness, capture, or because his or her whereabouts or condition cannot be determined.
- casualties,loss in numerical strength through any cause, as death, wounds, sickness, capture, or desertion.
- one who is injured or killed in an accident: There were no casualties in the traffic accident.
- any person, group, thing, etc., that is harmed or destroyed as a result of some act or event: Their house was a casualty of the fire.
- a serious accident, especially one involving bodily injury or death.
noun plural -ties
- a serviceman who is killed, wounded, captured, or missing as a result of enemy action
- a person who is injured or killed in an accident
- a hospital department in which victims of accidents, violence, etc, are treated
- anything that is lost, damaged, or destroyed as the result of an accident, etc
early 15c., “chance, accident; incidental charge,” from casual (adj.) on model of royalty, penalty, etc. Casuality had some currency 16c.-17c. but is now obsolete. Meaning “losses in numbers from a military or other troop” is from late 15c. Meaning “an individual killed, wounded, or lost in battle” is from 1844.