Translation guide
The act of walking or performing other activities while asleep. In Japanese, this is most commonly expressed with the noun 夢遊病 (むゆうびょう) or the verb phrase 夢遊病で歩く, but more natural, everyday expressions also exist.
To refer to sleepwalking as a phenomenon or a single instance.
The standard medical/formal term for sleepwalking. Can be used as a noun.
He has symptoms of sleepwalking.
Literally 'to walk due to sleepwalking illness'. A clear way to describe the action.
It seems I was sleepwalking last night.
A more colloquial way to say 'walk while half-asleep/drowsy'. 寝ぼける means to be still drowsy or not fully awake.
The child was walking around sleepwalking.
Literally 'walk while sleeping'. Simple and easily understood, but less idiomatic than 寝ぼけて歩く.
I can't believe you walk in your sleep.
To describe the action of sleepwalking.
The most direct verbal expression. Can be conjugated normally.
He often sleepwalks.
Common in casual speech. Implies a state of drowsiness rather than a medical condition.
A straightforward description, but can sound a bit literal.
I have a habit of sleepwalking.
夢遊病 is the clinical term and can sound formal or medical. 寝ぼけて歩く is more everyday and describes the groggy, half-asleep state. Use 夢遊病 when discussing the condition seriously, and 寝ぼけて歩く in casual conversation.
寝ぼける on its own means 'to be half-asleep' or 'to be drowsy'. It can be used for actions other than walking, like talking in your sleep (寝ぼけて話す).
Last night I was sleepwalking and almost fell down the stairs.