1

sleep

noun \ ˈslēp \

Definition of sleep

1 :the natural periodic suspension of consciousness during which the powers of the body are restored — compare REM sleep, slow-wave sleep
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
3 a :a period spent sleeping
b :night
c :a day's journey
4 :crusty matter present in the corner of an eye upon awakening

sleeplike

play \ˈslēp-ˌlīk\ adjective

Examples of sleep in a Sentence

  1. I just need to get some sleep.

  2. How much sleep did you get last night?

  3. Her roommate talks in her sleep.

  4. The noise woke her from a deep sleep.

  5. He woke up and rubbed the sleep out of his eyes.

Recent Examples of sleep from the Web

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.

Origin and Etymology of sleep

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

Other Physiology Terms


2

sleep

verb

Definition of sleep

slept play \ˈslept\; sleeping
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

Examples of sleep in a Sentence

  1. I couldn't sleep last night. I was awake all night long.

  2. I usually try to sleep for at least eight hours every night.

  3. Did you sleep soundly last night?

  4. We were sleeping peacefully when a sudden loud noise woke us up.

  5. I can never sleep on airplanes.

  6. The tent sleeps five adults.

Recent Examples of sleep from the Web

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

before 12th century

sleep Synonyms

Synonyms
catnap, doze, nap, rest, slumber, snooze
Related Words
drop off, drowse (off), nod off; oversleep, sleep in; dream, hibernate
Near Antonyms
arise, arouse, awake, rise, wake

SLEEP Defined for English Language Learners

sleep

noun

Definition of sleep for English Language Learners

  • : the natural state of rest during which your eyes are closed and you become unconscious

  • : a period of sleep especially of a particular kind

  • : the dry substance that sometimes forms in the corners of your eyes while you are sleeping


sleep

verb

Definition of sleep for English Language Learners

  • : 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 Defined for Kids

1

sleep

verb \ ˈslēp \

Definition of sleep for Students

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

2

sleep

noun

Definition of sleep for Students

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 3
  • The sick pet was put to sleep.

sleepless

\-ləs\ adjective

sleeplessness

noun

Medical Dictionary

1

sleep

noun \ ˈslēp \

medical Definition of sleep

1 :the natural periodic suspension of consciousness during which the powers of the body are restored — compare rem sleep, slow-wave sleep
2 :a state resembling sleep: as
a :death 1
  • put a pet cat to sleep
b :a state marked by a diminution of feeling followed by tingling
  • her foot went to sleep

2

sleep

intransitive verb

medical Definition of sleep

slept play \ˈslept\; sleeping
:to rest in a state of sleep


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