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
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
4
: crusty matter present in the corner of an eye upon awakening
slept
ˈslept 
; sleeping; sleeps
; sleeping; sleeps
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
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
Synonyms
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.
Recent Examples on the Web
Malia Griggs, SELF, 21 Nov. 2024
Iris noted that the global stress management and brain health supplements market is projected to reach about $15 billion by 2027, while the sleep aid market is expected to exceed $6 billion within the same time frame.
—Samantha Conti, WWD, 21 Nov. 2024
Scott Gilbertson, WIRED, 22 Nov. 2024
May help cushion your shoulders and hips, especially when sleeping on your side.
—Heather Cruickshank, SELF, 21 Nov. 2024
See all Example Sentences for sleep 
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Noun
Kitsch Satin Sleep Set This luxurious satin pillowcase sleep set will leave their hair frizz-free come morning.
—Malia Griggs, SELF, 21 Nov. 2024
Iris noted that the global stress management and brain health supplements market is projected to reach about $15 billion by 2027, while the sleep aid market is expected to exceed $6 billion within the same time frame.
—Samantha Conti, WWD, 21 Nov. 2024
Verb
Synthetic bags are generally the best budget sleeping options for those camping in the heat.
—Scott Gilbertson, WIRED, 22 Nov. 2024
May help cushion your shoulders and hips, especially when sleeping on your side.
—Heather Cruickshank, SELF, 21 Nov. 2024
See all Example Sentences for sleep
Articles Related to sleep
Dictionary Entries Near sleep
Cite this Entry
“Sleep.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/sleep. Accessed 3 Dec. 2024.
Copy CitationKids Definition
sleep
1 of 2 noun1
: the natural periodic loss of consciousness during which the powers of the body are restored
2
: a state resembling sleep: as
a
: a state of inactivity (as hibernation) like sleep
b
: death sense 4
put my pet cat to sleep
also
: coma entry 1, trance
c
: a state marked by loss of feeling followed by tingling
my foot's gone to sleep
sleep
2 of 2 verb
slept
ˈslept
; sleeping
; sleeping
1
: to rest or be in a state of sleep
2
: to get rid of or spend in or by sleep
slept off his headache
3
: to provide sleeping space for
the boat sleeps six
4
: to have sexual intercourse
Medical Definition
sleep
1 of 2 noun1
: 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
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