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; sleeps

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 was sleeping with a coworker — see also sleep together

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

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. See More
Recent Examples on the Web: Noun Not the Eat Pray Love kind, but with a newborn baby sleep was at a premium. Omaid Homayun, Forbes, 14 May 2022 What matters is whether gaming is interfering with kids’ sleep, physical activity, nutrition or grades, and whether the kids enjoy doing things with friends that don’t involve gaming. Julie Jargon, WSJ, 14 May 2022 Our seven-part guide has helpful hints to achieve better sleep. Jen Rose Smith, CNN, 10 May 2022 For a cooler sleep, go with the lightweight option filled with alpaca fiber known for its excellent temperature regulating properties. Emma Seymour, Good Housekeeping, 10 May 2022 Excessive alcohol use is also linked to injury, poor sleep, depression and a host of long-term health issues, including high blood pressure, heart disease, and some types of cancer. Kat Eschner, Fortune, 7 May 2022 Just as a bear might stretch after a long sleep, plants stretch through cold soil, hungry for spring rains and the warmth of the sun. Joshua Gunter, cleveland, 27 Apr. 2022 In an attempt to clear her mind over Malva’s allegations and the Ridge turning against her family, Claire puts herself into a deep sleep with ether. Sharareh Drury, Variety, 10 Apr. 2022 The problem is, every two or three weeks, Greg falls into a deep sleep that lasts three days. Abigail Van Buren, oregonlive, 3 Apr. 2022 Recent Examples on the Web: Verb Dakarai Singletary couldn’t sleep Saturday night, after the shooting at Tops Friendly Markets, a grocery store up the street from his home in Buffalo, New York. Claretta Bellamy, NBC News, 18 May 2022 Some group members could sleep while others kept watch. Elizabeth Preston, Smithsonian Magazine, 6 May 2022 The vast majority of the roughly 2,700-strong crew already sleep elsewhere, with about 400 living aboard. Matt Seyler, ABC News, 2 May 2022 With a volume of 499 GT, the spacious interior can sleep up to 12 guests across six cabins, as well as 11 crew within four cabins and a captain’s cabin. Rachel Cormack, Robb Report, 2 May 2022 Parents can sleep on the bottom and their little one can climb to the top if there are ever any nighttime fears. Mariah Thomas, Good Housekeeping, 1 May 2022 Oftentimes, Alzheimer’s impacts sleep patterns — causing those affected to stay awake during the night. Ebony Williams, ajc, 25 Apr. 2022 So tiny is the place that its whole is taken up when the family of four lays down to sleep at night. Rafia Zakaria, The New Republic, 5 May 2022 Volkswagen, Toyota and General Motors, who have major joint ventures with China’s huge SAIC Motor, were forced to scale back production and ask their local workers to sleep on site to isolate them from the pandemic. Peter Lyon, Forbes, 30 Apr. 2022 See More

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.

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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Dictionary Entries Near sleep

sleeky

sleep

sleep apnea

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Statistics for sleep

Last Updated

20 May 2022

Cite this Entry

“Sleep.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/sleep. Accessed 23 May. 2022.

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More Definitions for sleep

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

sleep

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

Medical Definition of sleep (Entry 2 of 2)

: to rest in a state of sleep

More from Merriam-Webster on sleep

Nglish: Translation of sleep for Spanish Speakers

Britannica English: Translation of sleep for Arabic Speakers

Britannica.com: Encyclopedia article about sleep

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