sleep

noun
\ ˈslēp How to pronounce sleep (audio) \

Definition of sleep

 (Entry 1 of 2)

1 : the natural, easily reversible periodic state of many living things that is marked by the absence of wakefulness and by the loss of consciousness of one's surroundings, is accompanied by a typical body posture (such as lying down with the eyes closed), the occurrence of dreaming, and changes in brain activity and physiological functioning, is made up of cycles of non-REM sleep and REM sleep, and is usually considered essential to the restoration and recovery of vital bodily and mental functions
2 : a state resembling sleep: such as
a : a state of torpid inactivity
b : death put a pet cat to sleep also : trance, coma
c : the closing of leaves or petals especially at night
d : a state marked by a diminution of feeling followed by tingling my foot's gone to sleep
e : the state of an animal during hibernation
3a : a period spent sleeping
b : night
c : a day's journey
4 : crusty matter present in the corner of an eye upon awakening

sleep

verb
slept\ ˈslept How to pronounce sleep (audio) \; sleeping

Definition of sleep (Entry 2 of 2)

intransitive verb

1 : to rest in a state of sleep
2 : to be in a state (as of quiescence or death) resembling sleep
3 : to have sexual relations usually used with with

transitive verb

1 : to be slumbering in slept the sleep of the dead
2 : to get rid of or spend in or by sleep sleep away the hours sleep off a headache
3 : to provide sleeping accommodations for the boat sleeps six

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Other Words from sleep

Noun

sleeplike \ ˈslēp-​ˌlīk How to pronounce sleep (audio) \ adjective

Synonyms & Antonyms for sleep

Synonyms: Noun

Synonyms: Verb

Antonyms: Noun

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Examples of sleep in a Sentence

Noun I just need to get some sleep. How much sleep did you get last night? Her roommate talks in her sleep. The noise woke her from a deep sleep. He woke up and rubbed the sleep out of his eyes. Verb I couldn't sleep last night. I was awake all night long. I usually try to sleep for at least eight hours every night. Did you sleep soundly last night? We were sleeping peacefully when a sudden loud noise woke us up. I can never sleep on airplanes. The tent sleeps five adults.
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Recent Examples on the Web: Noun No matter your sleeping style or budget, rest assured one of these mattresses will give you a good night’s sleep. Camryn Rabideau, Forbes, "10 Memory Foam Mattresses That Keep You Comfy Without Trapping Heat," 6 May 2021 Perry, an Orlando native, suffered cardiac arrest in his sleep and fell into a coma for weeks in 2007. Kathleen Christiansen, orlandosentinel.com, "‘Growing Bolder’ season 7 spotlights Central Florida residents," 4 May 2021 At the end, Grimes accidentally electrocutes himself, and then Homer snores and talks in his sleep at Grimes’s funeral, to the amusement of the attendees. Mike Sacks, The New Yorker, "John Swartzwelder, Sage of “The Simpsons”," 2 May 2021 Two judges expressed concern that light is flashed in Maxwell's cell at night, interrupting her sleep. Stephanie Pagones, Fox News, "Ghislaine Maxwell's brother calls lock-up a 'house of horrors'; judge seeks answers for alleged treatment," 30 Apr. 2021 With the $10 million in federal funding from the National Institutes of Health, Carskadon is indeed hoping to make advances in sleep. BostonGlobe.com, "New center in R.I. will research sleep, and how it affects kids’ mental health," 30 Apr. 2021 The woman later reported, on April 21, that two men from the Washington Boulevard home came to her house at 2 a.m. April 4 and knocked on her door, which woke the woman from her sleep. cleveland, "Woman loses $3,000 in Social Security scam: University Heights police blotter," 29 Apr. 2021 Jimmy Gibson – the swashbuckling, gifted and notoriously opinionated Cincinnati chef who died in his sleep on Wednesday at age 63 – had moved to Catawba Island late last year to be closer to his brother, who kept a fishing boat there. Keith Pandolfi, The Enquirer, "The swashbuckling legacy of Jimmy Gibson," 23 Apr. 2021 Nucalm has sleep-inducing stories, music and meditations for the whole family. oregonlive, "Is it time to shed some pandemic pounds and that built-up stress? 10 smart ways to eat, sleep better and build a workout plan before summer arrives," 6 Apr. 2021 Recent Examples on the Web: Verb Wonderland Camp, a sleep-away camp in Rocky Mount, Mo., was closed last year, disappointing the children and adults with disabilities who come for arts and crafts, talent shows and a formal dance, complete with a disco ball. New York Times, "‘Turning the Corner’: U.S. Covid Outlook Reaches Most Hopeful Point Yet," 6 May 2021 Your circadian clock regulates a number of functions in your body, most famously the sleep-wake cycle. Emily P.g. Erickson, Wired, "Here’s a Calendar Trick to Ease Post-Pandemic Reentry," 6 May 2021 Women line-dried the laundry in the courtyard, where the children would sleep on bamboo sheets on hot summer nights. Han Zhang, The New Yorker, "The Second Life of Yi Lei’s Poetry," 5 May 2021 People have forced their way into her building, and sleep under tarps in the yard. Zoë Jackson, Star Tribune, "St. Paul weighs future of homeless drop-in center as neighbors, businesses complain," 5 May 2021 There’s also lectures on how to play poker, train your dog and even sleep better. Nishka Dhawan, USA TODAY, "MasterClass is offering 2 memberships for the price of one for Mother's Day 2021," 5 May 2021 One thing the new mom on our list could definitely use: sleep. Kimberly Wilson, Essence, "8 Gifts That New and Expecting Moms Will Appreciate This Mother’s Day," 4 May 2021 Lawsuit settlements have led to the city creating a storage area for homeless people to use and permission for homeless people to sleep outdoors between 9 p.m. and 5:30 a.m. Gary Warth, San Diego Union-Tribune, "Attorney demands Oceanside stop closing homeless encampments," 3 May 2021 This is consistent with research showing a relationship between elevated cortisol, a stress hormone, and sleep loss. Washington Post, "Good sleep means more than getting enough hours. A consistent schedule matters, too.," 30 Apr. 2021

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'sleep.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of sleep

Noun

before the 12th century, in the meaning defined at sense 1

Verb

before the 12th century, in the meaning defined at intransitive sense 1

History and Etymology for sleep

Noun

Middle English slepe, from Old English slǣp; akin to Old High German slāf sleep and perhaps to Latin labi to slip, slide

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Time Traveler for sleep

Time Traveler

The first known use of sleep was before the 12th century

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Statistics for sleep

Last Updated

8 May 2021

Cite this Entry

“Sleep.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/sleep. Accessed 14 May. 2021.

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More Definitions for sleep

sleep

noun

English Language Learners Definition of sleep

 (Entry 1 of 2)

: the natural state of rest during which your eyes are closed and you become unconscious
: a period of sleep especially of a particular kind
informal : the dry substance that sometimes forms in the corners of your eyes while you are sleeping

sleep

verb

English Language Learners Definition of sleep (Entry 2 of 2)

: to rest your mind and body by closing your eyes and becoming unconscious
: to have enough space for (a specified number of people) to sleep in it

sleep

verb
\ ˈslēp How to pronounce sleep (audio) \
slept\ ˈslept \; sleeping

Kids Definition of sleep

 (Entry 1 of 2)

: to rest with eyes closed in a temporary state of inactivity : be or lie in a state of sleep The baby is sleeping.

sleep

noun

Kids Definition of sleep (Entry 2 of 2)

1 : a natural temporary state of rest during which an individual becomes physically inactive and unaware of the surrounding environment and many bodily functions (as breathing) slow
2 : an inactive state (as hibernation) like true sleep
3 : death sense 3 The sick pet was put to sleep.

Other Words from sleep

sleepless \ -​ləs \ adjective
sleeplessness noun

sleep

noun
\ ˈslēp How to pronounce sleep (audio) \

Medical Definition of sleep

 (Entry 1 of 2)

1 : the natural, easily reversible, periodic state of many living things that is marked by the absence of wakefulness and by the loss of consciousness of one's surroundings, is accompanied by a typical body posture (as lying down with the eyes closed), the occurrence of dreaming, and changes in brain activity and physiological functioning, is made up of cycles of non-REM sleep and REM sleep, and is usually considered essential to the restoration and recovery of vital bodily and mental functions
2 : a state resembling sleep: as
a : death sense 1 put a pet cat to sleep
b : a state marked by a diminution of feeling followed by tingling her foot went to sleep
slept\ ˈslept How to pronounce sleep (audio) \; sleeping

Medical Definition of sleep (Entry 2 of 2)

: to rest in a state of sleep

Comments on sleep

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