What does somnambulism mean?
Somnambulism is the formal term for sleepwalking, a condition in which a person walks or performs other complex movements while apparently asleep. The word is especially common in medical, literary, and historical writing, whereas sleepwalking is the everyday term used by most speakers. Somnambulism can involve simple actions, such as wandering through a house, but reports also describe more elaborate behavior, including travel or complex tasks. Because the sleeper may have little or no awareness of the activity, it can be concerning to observers and sometimes dangerous. The condition is generally discussed as a sleep-related disorder rather than as a deliberate habit. Somnambulism is also valued as a vivid literary word because it conveys both the mystery of apparently unconscious movement and the unsettling idea that the body may act independently of conscious awareness.
nounThe condition of walking, or sometimes performing other complex movements, while apparently asleep; sleepwalking.
- The condition of walking or performing other complex movements while apparently asleep; sleepwalking.
"The historical accounts describe a striking case of somnambulism in which the sleeper traveled considerable distances without becoming fully awake."
"Her doctor suspected that the episodes of somnambulism were triggered by disrupted sleep."
"The novel uses somnambulism as a symbol of a character returning unconsciously to a troubling past."
Usually uncountable when referring to the condition; the plural is uncommon and is more likely to refer to separate reported episodes or cases.
"Accounts of somnambulisms in children are uncommon, but the phenomenon has long been documented."
Somnambulism is the formal word for sleepwalking: the sleeper can apparently walk, navigate, and even perform surprisingly complex actions while still asleep.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does somnambulism come from?
Somnambulism comes from Latin somnus, meaning “sleep,” and ambulare, meaning “to walk,” so its literal sense is “sleep-walking.” The term was borrowed into English through Latin and Neo-Latin usage in the early modern period. English relatives include somnambulant and somnambulate, while more distant cognates include ambulate and ambulatory, all based on the same Latin verb for walking.
Related word forms
How somnambulism is actually used
The term is formal and chiefly literary, medical, or historical. In ordinary conversation, sleepwalking is much more common.
Easily confused with somnambulism
Somnambulism and somnambulance both refer to sleepwalking, although somnambulance is the less common and more literary term.