lights-out

• 指规定的就寝时间或熄灯时间，也可指军队中命令关灯的号声或信号。

A noun referring to a designated time for going to bed, or a military signal indicating that lights must be turned off.

不可数

1. Prescribed bedtimeB1formal

   A designated time when lights must be turned off, typically for sleep, especially in institutions like schools or camps.

   熄灯时间

   • Lights-out at the summer camp is at 10 PM.
   • The dormitory enforces a strict lights-out policy.
   • After lights-out, no talking is allowed in the hallways.

   同义词bedtimecurfew

2. Military signalB2formal

   A signal, often a bugle call or command, indicating that all lights must be extinguished for the night.

   熄灯号

   • The bugler played the lights-out call at sunset.
   • After lights-out, the soldiers were confined to their barracks.
   • The commanding officer announced lights-out over the intercom.