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Definition of combat fatigue
: post-traumatic stress disorder occurring under wartime conditions (such as combat) that cause intense stress : battle fatigue, shell shock Nearly a half-million American soldiers were battle casualties during the fighting in Europe; by 1945 another 111,000 neuropsychiatric cases—then usually called combat fatigue—had been treated.— Roger J. Spiller The psychological strain he continues to endure has had many names over the years. In World War I, it was shell shock. In World War II, it was combat fatigue …— Steven Lee Meyers
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The first known use of combat fatigue was in 1943
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