also: ふしんばん
sleepless vigil; night watch
Refers to staying awake all night to keep watch, often in a military, security, or traditional context. Can also imply general vigilance.
The soldiers stood a sleepless vigil.
I was ordered to keep night watch.
寝ずの番 is a more colloquial phrase with the same meaning, literally 'watch without sleeping'.
Standard kanji spelling. The reading ねずばん is the most common.
Alternate reading, less common. May be encountered in older or formal contexts.
Formed from 寝ず, the negative continuative form of 寝る “sleep,” and 番 “watch, guard duty”: literally, a watch kept without sleeping. The spelling 不寝 represents 寝ず semantically.