bedtime; time to go to bed
Refers to the time when one goes to bed or should go to bed. Often used in daily routines, especially with children.
The children's bedtime is 9 o'clock.
It's already time to go to bed.
Lights-out time, typically in a dormitory or camp setting, not necessarily the same as personal bedtime.
Compound of 寝る (neru, 'to sleep') and 時間 (jikan, 'time'). A straightforward modern Japanese phrase.