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 slept (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 sleeplike (audio) \ adjective

Synonyms & Antonyms for sleep

Synonyms: Noun

bed, catnapping, dozing, napping, repose, rest, resting, shut-eye, slumber, slumbering, snoozing, z's (or zs)

Synonyms: Verb

catnap, doze, nap, rest, slumber, snooze

Antonyms: Noun

consciousness, wake, wakefulness

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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

Many factors could be contributing to the deadly trend among teens, including a chronic lack of sleep, an overuse of social media, even a fear of climate change. Sandee Lamotte, CNN, "Fast food may contribute to teen depression, study says," 29 Aug. 2019 To her, such a policy loses sight of how restorative sleep can be for a patient. Dominic Fracassa, SFChronicle.com, "SF General relaxes policy that tries to keep psychiatric ER patients awake to shorten visits," 28 Aug. 2019 Intermittent fasting overall can also lead to muscle loss, poor sleep, and rebound overeating. Maggie O'neill, Health.com, "What is Alternate-Day Fasting, and is it Even Safe? Here's What Nutritionists Have to Say," 28 Aug. 2019 Our common understanding is that sleep is a necessity and that use of soap prevents the spread of germs that cause diseases. Melissa Howell, Quartz, "How America’s bad eating habits impact kids in detention centers," 26 Aug. 2019 The sessions include such topics as navigating longer lives; exercise and you; sleep, healthy eating and hydration; financial fitness; advance planning; healthy relationships; medication management; community engagement and fall prevention. cleveland.com, "Summer comes alive through cardboard and paper: Olmsted Dates and Data," 23 Aug. 2019 Detained migrant children must have access to soap and toothpaste, and cannot be deprived of sleep, a panel of federal judges ruled Thursday. Graham Kates, CBS News, "Court says detained migrant children can't be sleep-deprived, must get soap," 15 Aug. 2019 By night two everyone should be so tired that sleep is no longer an issue, right? Milwaukee Journal Sentinel, "No cooler is needed for these easy, kid-friendly campsite meals," 14 Aug. 2019 Check out our roundup here A good night's sleep is crucial to enjoying being in the outdoors. James Lynch, Popular Mechanics, "The Ultimate Camping Checklist (So You're Prepared for Anything)," 10 Aug. 2019

Recent Examples on the Web: Verb

Retirement gives you the chance to sleep late and avoid the morning commute. The Economist, "People are working longer for reasons of choice and necessity," 2 Sep. 2019 Mice genetically engineered to have this mutation slept, on average, 1 hour less per day than controls, the researchers report online today in Neuron. Kelly Servick, Science | AAAS, "This genetic mutation makes people feel rested on just 6 hours of sleep," 28 Aug. 2019 Roughly 30 percent of the boat will stay original, including the galley, the bathroom, or head, and the berths where Steinbeck and the others slept. Smithsonian, "John Steinbeck’s Epic Ocean Voyage Rewrote the Rules of Ecology," 22 Aug. 2019 Bowles pleaded guilty to first-degree murder in 1996 for killing Walter Hinton in Jacksonville Beach, Florida by dropping a 40-pound cement stepping stone onto his sleeping head. Eric Levenson, CNN, "Florida set to execute serial killer who targeted gays across Southeast," 22 Aug. 2019 One of the most famous looks like a sleeping baby elephant. USA Today, "Were Wanda Tucker’s ancestors America’s first slaves? A difficult search for answers in far-away Angola," 22 Aug. 2019 In the last case, another woman sleeping near the victim awoke during the attack and fought Brotherton off with her own knife, according to court records. oregonlive.com, "Suspect in 2 knifepoint Portland sex assaults now accused in 3rd case," 22 Aug. 2019 Dates of conversations, moods after pickup, sleeping patterns, eating habits, decreased interest in play or other activities that your son once enjoyed . . . Meghan Leahy, Washington Post, "After his parents’ rough divorce, why is this previously chatty 4-year-old clamming up?," 21 Aug. 2019 So this week, the San Mateo City Council unanimously approved a plan to convert a portion of an old fire station into a sleeping barracks for far-flung officers who can’t afford the average $1.4 million Peninsula home. Taylor Kate Brown, SFChronicle.com, "Bay Briefing: The cops that sleep in their cars," 21 Aug. 2019

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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Statistics for sleep

Last Updated

7 Sep 2019

Look-up Popularity

Time Traveler for sleep

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

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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 slept (audio) \; sleeping

Medical Definition of sleep (Entry 2 of 2)

: to rest in a state of sleep

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More from Merriam-Webster on sleep

Rhyming Dictionary: Words that rhyme with sleep

Thesaurus: All synonyms and antonyms for sleep

Spanish Central: Translation of sleep

Nglish: Translation of sleep for Spanish Speakers

Britannica English: Translation of sleep for Arabic Speakers

Britannica.com: Encyclopedia article about sleep

Comments on sleep

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authorized for issue (as a bond)

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