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

Habit changes: Reduce your stress, don’t smoke and get seven to nine hours of sleep every night. Ladan Nikravan Hayes, Cincinnati.com, "‘Let’s Talk’: These traits increase the risk of developing breast cancer," 26 June 2019 People wanna finish a race, and especially a long one, and just lay on a couch or go to sleep. Tim Ferriss, Outside Online, "How Amelia Boone Trains, Eats, and Wins," 25 June 2019 On Sunday, Loyd was operating on about three hours of sleep. Beth Bragg, Anchorage Daily News, "Fueled by coffee and Red Bulls, Anchorage softball players celebrate solstice with a tournament," 25 June 2019 The captain, a 26-year-old Norwegian, went to sleep about 1 a.m., leaving a novice seaman at the helm. Bonnie Gross, sun-sentinel.com, "Boat tours explore underwater Biscayne National Park," 20 June 2019 But when her son was born in 2003, anxiety gripped her, robbing her of sleep. Shari Rudavsky, Indianapolis Star, "There's a new drug for postpartum depression, but wait till you see the price tag," 20 June 2019 In a fearless final twist, Ramy goes to sleep and dreams of Osama Bin Laden (Christopher Tramantana), and their conversation combines out-there weird comedy with fearful terror. Darren Franich, EW.com, "Emmys 2019: Consider Ramy Youssef for writing, directing, and starring in Ramy," 13 June 2019 But a sheet that fits well provides a smooth surface, greater comfort and a better chance for uninterrupted sleep. Hannah Morrill, ELLE Decor, "The Best Luxury Sheets For the Perfect Night's Sleep," 15 Nov. 2018 Alice is put to sleep before the measurement is made, knowing she will be wheeled into one of two identical rooms depending on the outcome. Quanta Magazine, "Why the Many-Worlds Interpretation Has Many Problems," 18 Oct. 2018

Recent Examples on the Web: Verb

Studies have shown that warm sleeping environments can interfere with circadian temperature regulation by preventing the body from reducing its internal thermostat, leading to poor sleep. Samantha Lauriello, Health.com, "This Is the Best Temperature for Sleeping, According to Experts," 9 July 2019 The fantasy adventure film picks up several years after the 2014 movie, which told the origin story of how Maleficent (Angelina Jolie) became a notorious villain and came to put a sleeping curse on Aurora (Elle Fanning). Katherine Schaffstall, The Hollywood Reporter, "Angelina Jolie and Michelle Pfeiffer Battle Over Elle Fanning in 'Maleficent: Mistress of Evil' Trailer," 8 July 2019 Overnight skies will be mostly clear and temps will dip to the low 60s, offering comfortable sleeping conditions. Cliff Pinckard, cleveland.com, "Monday brings brief break from heat, humidity: Cleveland, Akron weather forecast," 7 July 2019 The $15 million contract for the facility also calls for showers, toilets, sinks and sleeping mats, among other resources. Chelsea Curtis, azcentral, "Border Patrol officials unveil new Yuma facility designed to hold more migrants," 28 June 2019 Soon the girl and more than 200 other children up to age 17 were bused to another U.S. Customs and Border Protection facility on the north side of El Paso, a more temporary, tent-like facility with showers and sleeping mats. Washington Post, "Girl who was in gov’t custody inconsolable, lawyer says," 26 June 2019 The hardest part about leaving home is foregoing your favorite sleeping comforts. Megan Barber, Curbed, "Brilliant travel accessories that make hotel rooms feel like home," 21 June 2019 New pads promise to make such sleeping arrangements more comfortable, lighter, cheaper, or considerably easier to transport than ever before. Wes Siler, Outside Online, "Couples Camping Gear Just Got Even Better," 20 June 2019 Your work, activities, stature in the community, and even sleeping arrangements are dictated by your season. Alissa Wilkinson, Vox, "Midsommar is a brutish, nasty daylight nightmare from the director of Hereditary," 20 June 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

13 Jul 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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