寝不足(ねぶそく)

昨日(きのう)は徹夜(てつや)をしたので寝不足(ねぶそく)だ。

I have a lack of sleep because I stayed up all night yesterday. {lack of sleep}

残業(ざんぎょう)のせいで寝不足(ねぶそく)な日(ひ)が続(つづ)いている。

I've been having consecutive days of lack of sleep due to overtime work. {lack of sleep}

寝不足(ねぶそく)で試験(しけん)に臨(のぞ)んだので、結果(けっか)は散々(さんざん)でした。

Since I faced the exam with a lack of sleep, the result was disastrous. {lack of sleep}

クラスメイト：「昨日(きのう)徹夜(てつや)で課題(かだい)をしたから今日(きょう)は寝不足(ねぶそく)なんだ…。」

Classmate: "I stayed up all night doing homework yesterday, so I'm suffering from lack of sleep today..." {lack of sleep}

ある学者(がくしゃ)が寝不足(ねぶそく)の毎日(まいにち)が続(つづ)くとイライラしやすくなると唱(とな)えています。

A certain scholar is advocating that if you continue to have a lack of sleep every day, you become more prone to irritation. {lack of sleep}