Translation guide
Ways to express the act of falling asleep in Japanese, from neutral to casual and formal contexts.
To express the act of falling asleep in a neutral, everyday manner.
A natural, slightly literary way to say 'fall asleep'. It emphasizes the transition into sleep.
昨夜はすぐに眠りについた。
Last night I fell asleep right away.
A common verb meaning 'to fall asleep', often used for the moment of drifting off.
子供はすぐに寝入った。
The child fell asleep quickly.
Means 'to fall asleep', often implying settling into sleep, sometimes used for babies or when sleep comes after difficulty.
赤ちゃんがやっと寝付いた。
The baby finally fell asleep.
To say 'fall asleep' in casual conversation.
Casual contraction of 寝てしまう, meaning to fall asleep (often unintentionally).
テレビ見てたら寝ちゃった。
I fell asleep while watching TV.
Slang for 'falling asleep unintentionally', especially while doing something like gaming or studying.
昨夜、勉強中に寝落ちした。
Last night I fell asleep while studying.
To express 'falling asleep' in formal or written contexts.
Formal verb meaning 'to go to bed' or 'to fall asleep'. Used in official contexts or writing.
毎晩10時に就寝しています。
I go to sleep at 10 every night.
Literary expression for 'falling into sleep', often used in narratives.
彼は深い眠りに落ちた。
He fell into a deep sleep.
To express falling asleep without meaning to, or dozing off.
Onomatopoeic phrase for dozing off or nodding off, often while sitting.
会議中にうとうとしてしまった。
I dozed off during the meeting.
To doze off or nap unintentionally, especially in a place where one shouldn't sleep.
電車で居眠りして、乗り過ごした。
I dozed off on the train and missed my stop.
To express trouble falling asleep.
Negative potential form of 寝付く, meaning 'cannot fall asleep'.
昨夜は暑くて寝付けなかった。
Last night I couldn't fall asleep because it was hot.
General phrase for 'cannot sleep', which implies difficulty falling asleep or staying asleep.
心配事があって眠れない。
I have worries and can't sleep.
寝入る focuses on the moment of falling asleep. 寝付く often implies settling into sleep, especially for children or after difficulty. 眠りにつく is slightly more literary and describes the transition into sleep.
子供はすぐに寝入った。
The child fell asleep quickly.
赤ちゃんがやっと寝付いた。
The baby finally fell asleep.
静かな夜に眠りについた。
I fell asleep on a quiet night.
Avoid directly translating 'fall' as 落ちる in most contexts. 眠りに落ちる is literary and not used in daily conversation. Use 寝入る or 眠りにつく instead.