the.com/casualty

A person killed, injured, or lost in an accident, disaster, or conflict; in military use, anyone removed from service by harm.

means A person hurt, killed, or lost as a result of an accident, disaster, or conflict.

from Traces back to Latin casus, 'a falling, chance occurrence' — the same root behind 'case' and 'occasion.' Through French casuel and Middle English, 'casualty' first meant simply chance or accident, something that befalls you. Only later did it narrow to its grim military sense: the person to whom the bad chance actually happened.

scope creep
includes wounded and missing, not just dead
etymology
from casual, meaning happening by chance
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