godan verb (-ru), intransitive verb
fall asleep; go to sleep; be asleep
Describes a state where everyone in a place has gone to sleep and it has become quiet. Often used for nighttime scenes in houses, neighborhoods, or towns.
夜が更けて、町はすっかり寝静まっていた。
The night grew late and the town was completely asleep.
家
After his family had fallen asleep, he quietly slipped out of the house.