re ‧ veil ‧ le /rɪˈvæli $ ˈrevəli/ BrE AmE noun [singular, uncountable]
[ Date: 1600-1700 ; Language: French ; Origin: réveillez! 'wake up!' , from réveiller 'to wake up' , from Latin vigilare 'to stay awake' ]
a special tune played as a signal to wake soldiers in the morning, or the time at which it is played