sleepwalking

UK: /ˈsliːpˌwɔːkɪŋ/ US: /ˈslipˌwɔkɪŋ/ ,(slēp′wô′king)

WordReference Random House Learner's Dictionary of American English © 2025

sleep•walk•ing /ˈslipˌwɔkɪŋ/   n. [uncountable]

1. Pathology the act of walking while asleep;
   somnambulism.

sleep•walk, v. [no object]
sleep•walk•er, n. [countable]

WordReference Random House Unabridged Dictionary of American English © 2025

sleep•walk•ing  (slēp′wô′king), n. 

1. Physiology the act or state of walking, eating, or performing other motor acts while asleep, of which one is unaware upon awakening;
   somnambulism.

adj. 

2. Physiology of or pertaining to the state of walking while asleep;
   somnambulistic.

• sleep + walking 1790–1800

sleep′walk′er, n. 

WordReference Random House Unabridged Dictionary of American English © 2025

sleep•walk  (slēp′wôk′), v.i. 

1. Physiology to engage in sleepwalking.

n. 

2. Physiology an act of sleepwalking;
   somnambulation.

• back formation from sleepwalking 1920–25

Collins Concise English Dictionary © HarperCollins Publishers::

sleepwalk / ˈsliːpˌwɔːk/ verb (intransitive)

1. to walk while asleep
   See also somnambulism
2. (often followed by into or through) to act or proceed without thinking about what one is doing

ˈsleepˌwalker noun

ˈsleepˌwalking noun , adjective