A military signal or bugle call played early in the morning to wake soldiers; also used for any morning waking signal.
From French 'reveille,' derived from 'réveiller' meaning 'to wake up,' from 're-' (again) and 'veiller' (to watch or stay awake). Military term adopted into English in the 1600s.
Reveille literally means 'wake up' in French—the bugle call is just a musical version of someone yelling that word, and every soldier who wakes to it is hearing 400-year-old French.
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