a. The sounding of a bugle early in the morning to awaken and summon people in a camp or garrison.
b. This bugle call or its equivalent.
c. The first military formation of the day.
2. A signal to get up out of bed.
[Alteration of French réveillez, second person pl. imperative of réveiller, to wake, from Old French resveiller : re-, re- + esveiller, to awake (from Vulgar Latin *exvigilāre : Latin ex-, ex- + Latin vigilāre, to awake, from vigil, awake; see weg- in the Appendix of Indo-European roots).]
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