lights-out
US /ˈlaɪts.aʊt/
UK /ˈlaɪts.aʊt/

1.
熄燈時間, 就寢時間
the time when lights are to be extinguished, especially in a military camp or dormitory
:
•
At lights-out, all soldiers must be in their bunks.
熄燈時,所有士兵必須回到各自的鋪位。
•
The warden announced lights-out at 10 PM.
典獄長宣布晚上10點熄燈。