From Longman Dictionary of Contemporary Englishbattle fatigueˈbattle faˌtigue noun [uncountable] old-fashioned MIMPa type of mental illness caused by the frightening experiences of war, in which someone feels very anxious and upset
Examples from the Corpus
battle fatigue• If battle fatigue sets in, Mr Biedenkopf may have reason for optimism.• A lifeless performance left manager Lennie Lawrence wondering whether his players are suffering battle fatigue after a hectic cup-and-league programme. 