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

Welcome to the world of competition barbecue, where cooks go to great lengths — including getting just a few hours of sleep — to ensure that their ribs, brisket, chicken and pork are the most tender and flavorful meats on the block. Sarah Kuta, The Denver Post, "Barbecue becomes a competitive sport as cooks go to great lengths to win the Colorado BBQ Challenge," 6 June 2019 At the start of the book, gaming titan Dodge Forthrast is punching the snooze button for nine more minutes of sleep. Jim Kiest, ExpressNews.com, "12 new books for your summer reading list," 5 June 2019 A few hours of sleep and some sardines and crackers found us in good spirits, ready to plow snow for another 3 miles, where the trail would drop out of the snowline. Steve Meyer, Anchorage Daily News, "Years later, a loosely planned adventure is remembered for its laughs and lessons," 5 June 2019 Even more than even exercise, sleep is the gas for my tank, what puts me in a position to more clearly see everything else that needs to be done and be able to think strategically about approaching it. Marisa Lascala, Good Housekeeping, "Putting Your Family First Doesn’t Make You a Better Mom," 14 Jan. 2019 Of course, the sheets between which you sleep are a matter of personal preference. Kelsey Keith, Curbed, "My holy grail bed sheets—that friends also love," 23 Aug. 2018 From May 23 through May 27, get 40 percent off apparel, accessories, sleep, and swim. Tiffany Dodson, SELF, "The Best Memorial Day 2019 Beauty and Fashion Sales From Your Favorite Brands," 23 May 2019 Her newest brand, NormaLife, will include a skincare collection and products focused on healthy living (specifically, three pillars: sleep, diet, and exercise) are on the way. Jennifer Goldstein, Marie Claire, "Norma Kamali Doesn’t Want Investment Money or a Makeover," 13 May 2019 Serotonin regulates mood, emotion, sleep, and appetite, while epinephrine controls the body's response to stress and dopamine helps produce smooth physical movements. Carolyn Twersky, Seventeen, "Can You Really Have a Serial Killer Gene like Betty on "Riverdale"?," 9 May 2019

Recent Examples on the Web: Verb

Inside the halls of Tulsa’s Nathan Hale High School, pregnant and expectant youth gathered with a counselor to learn safe sleeping tips for their babies on the way. Janna Zinzi, Teen Vogue, "For Teen Parents in Tulsa, Respect in School Is the Key to Success," 29 May 2019 Harrer and his party, hauling knapsacks, hardware and ropes, scaled the sheer precipice over four days—eating, sleeping, brewing coffee on ledges so narrow in... Susan Froderberg, WSJ, "Five Best: Susan Froderberg on Extraordinary Mountain Ascents," 8 Mar. 2019 Lesser known than other systems in the body (like cardiovascular or respiratory), the ECS is critical for eating, sleeping, relaxing, and protecting our bodies from harm. Kaitlyn Pirie, Woman's Day, "What Is CBD, and Why Is Everybody Talking About It?," 15 Feb. 2019 He was born with just two settings, full throttle, then sleep. Lauren Hubbard, Town & Country, "Read the Full Transcript of President George W. Bush's Eulogy for His Father," 5 Dec. 2018 Many travelers, though, shared photos of others sleeping on the floor and on top of suitcases—and reported poor communication from the airline as to what they were supposed to do next. Meredith Carey, Condé Nast Traveler, "This Flight Was Delayed for 3 Days—Here's Everything That Went Wrong," 5 Nov. 2018 Marchionne was a famous workaholic, often reportedly sleeping on his private plane between meetings in the US and Europe. Jonathan M. Gitlin, Ars Technica, "Sergio Marchionne, the man who saved Fiat Chrysler, dies at 66," 25 July 2018 Sometimes they're soothed by the feeling of my baby kicking or the peaceful look on my sleeping husband’s face. Allison Mcgevna, Glamour, "It’s Beyond Refreshing That Even Beyoncé Experiences Self-Doubt as a Mother," 17 Apr. 2019 Getty Images The night before his royal wedding to Kate Middleton, Prince William could barely sleep. Kayleigh Roberts, Marie Claire, "Why Prince William Couldn't Sleep the Night Before His Wedding to Kate Middleton," 13 Apr. 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

15 Jun 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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