somnambulate

1 of 2

verb

som·​nam·​bu·​late säm-ˈnam-byə-ˌlāt How to pronounce somnambulate (audio)
somnambulated; somnambulating

intransitive verb

: to walk when asleep
somnambulation
(ˌ)säm-ˌnam-byə-ˈlā-shən How to pronounce somnambulate (audio)
noun

somnambulation

2 of 2

noun

som·​nam·​bu·​la·​tion
: the action of walking in sleep

Word History

Etymology

Noun

New Latin somnambulation-, somnambulatio, from somnambul- + Latin -ation-, -atio -ation

First Known Use

Verb

1833, in the meaning defined above

Time Traveler
The first known use of somnambulate was in 1833

Browse Nearby Words

somnambular
somnambulate
somnambulation
See all Nearby Words

Cite this Entry

“Somnambulate.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/somnambulate. Accessed 8 Jul. 2026.

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Medical Definition

somnambulate

intransitive verb
som·​nam·​bu·​late -ˌlāt How to pronounce somnambulate (audio)
somnambulated; somnambulating
: to walk while asleep
somnambulation
-ˌnam-byə-ˈlā-shən How to pronounce somnambulate (audio)
noun
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