noun \ˈslēp\

: 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

Full Definition of SLEEP

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

Examples of SLEEP

  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.

Origin of SLEEP

Middle English slepe, from Old English slǣp; akin to Old High German slāf sleep and perhaps to Latin labi to slip, slide
First Known Use: before 12th century

Other Physiology Terms

eructation, flux, gustatory, menarche, myopia, senescence, torpor



: 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

slept \ˈslept\ sleep·ing

Full Definition of SLEEP

intransitive verb
:  to rest in a state of sleep
:  to be in a state (as of quiescence or death) resembling sleep
:  to have sexual relations —usually used with with
transitive verb
:  to be slumbering in <slept the sleep of the dead>
:  to get rid of or spend in or by sleep <sleep away the hours> <sleep off a headache>
:  to provide sleeping accommodations for <the boat sleeps six>

Examples of SLEEP

  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.

First Known Use of SLEEP

before 12th century
May 29, 2015
bodacious Hear it
unmistakable, remarkable, or voluptuous
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