sleep

sleep — verb

1. to go into a natural state of rest at night, during which your eyes stay closed

1.verbintransitiveA1
Definition

to go into a natural state of rest at night, during which your eyes stay closed and you are not aware of what is happening around you.

Example

Sahil usually sleeps for about eight hours every night.

sleep + for + duration

The baby finally slept through the whole night without crying.

sleep through the night

Common collocations
  • sleep well
  • sleep badly
  • sleep deeply
  • sleep peacefully
  • sleep through the night
  • sleep for hours
Synonyms
  • doze

    a lighter, shorter sleep, often in a chair or during the day

  • slumber

    more literary or formal; suggests peaceful, deep sleep

  • nod off

    informal; means to start sleeping accidentally, especially when sitting

Antonyms

Grammar Patterns

sleep

sleep + adverb of place/time

Usage Note

This is the basic, most common meaning. It is primarily intransitive — you do not 'sleep something'. The exception is the fixed pattern 'sleep a ... sleep' (e.g. 'sleep a good sleep').

Common Mistakes

I slept very much last night.
I slept for a long time last night.
'sleep' does not take 'much' as a direct object; use 'sleep for + duration'.
I need to asleep.
I need to sleep.
'asleep' is an adjective; 'sleep' is the verb.

2. when a room, vehicle, or tent contains beds for a given number of people, the ve

2.verbtransitiveB1
Definition

when a room, vehicle, or tent contains beds for a given number of people, the verb 'sleep' is used to describe its capacity — for instance, a cabin that sleeps four people has beds for four.

Example

The cabin sleeps six people, with two bunk beds and a sofa bed.

building/room sleeps + number

Their large family tent sleeps four adults comfortably.

Common collocations
  • sleeps four
  • sleeps six
  • sleeps up to
Synonyms
  • accommodate

    broader meaning; includes sleeping, sitting, or housing in general

  • hold

    less formal; used for rooms, vehicles, and containers

Grammar Patterns

sleep + number of people

Usage Note

Only used with a number or quantity. You cannot say 'This tent sleeps people' — you must say how many. The subject is always a place or vehicle, never a person.

Common Mistakes

This sofa sleeps.
This sofa sleeps two people.
The verb must be followed by a number indicating capacity.

3. to experience a particular quality or type of sleep, especially in terms of how

3.verbintransitiveA2
Definition

to experience a particular quality or type of sleep, especially in terms of how well or how long you rest.

Example

Adina slept badly last night because of the noise from the street.

sleep + badly

After a long walk in the mountains, Liang slept deeply for ten hours.

sleep + deeply

Common collocations
  • sleep well
  • sleep badly
  • sleep deeply
  • sleep soundly
  • sleep peacefully
  • sleep poorly

Grammar Patterns

sleep + adverb (well, badly, deeply, soundly)

Usage Note

Unlike the core sense (verb/1), this sense must be followed by an adverb describing the quality of sleep. On its own, 'I slept' does not belong to this sense — it belongs to sense 1.

4. to postpone making a final choice until after a night of rest, allowing extra ti

4.verbintransitiveB2
Definition

to postpone making a final choice until after a night of rest, allowing extra time for careful thought.

Example

I am not sure whether to accept the job offer, so I will sleep on it.

sleep on it (idiomatic)

Yasmin told her partner she needed to sleep on the proposal before giving an answer.

Common collocations
  • sleep on it
  • sleep on the idea
  • sleep on the offer
  • sleep on the decision
Synonyms
Antonyms

Grammar Patterns

sleep on it

sleep on + noun phrase

Usage Note

Always used with 'on' as a phrasal verb. The decision is typically an important one — job offers, purchases, relationship choices. This is a fixed idiomatic expression.

Common Mistakes

I will sleep on it about the price.
I will sleep on the price.
Do not add 'about' after 'sleep on'; the thing being decided goes directly after 'on'.

5. to fail to notice or appreciate the true value or importance of someone or somet

5.verbtransitiveB2
Definition

to fail to notice or appreciate the true value or importance of someone or something, often missing a good opportunity as a result.

Example

Do not sleep on that band — their new album is truly amazing.

negative imperative: don't sleep on

Lakan slept on the warning signs until it was too late to fix the problem.

Common collocations
  • don't sleep on
  • sleep on someone
  • sleep on something
Synonyms
Antonyms
  • recognize

    to acknowledge the value or importance of something

Grammar Patterns

sleep on + noun phrase (in negative imperative)

Usage Note

Common in informal and slang contexts, especially in recommendations ('don't sleep on X'). This sense is different from verb/4 ('sleep on it' = delay a decision) — here 'sleep on' means 'ignore or overlook'.

Common Mistakes

❌ 'Don't sleep on it — make a choice now.' — Confusing this sense with verb/4 (DELAY DECISION). This sense criticizes ignoring value, not postponing a decision.

6. to spend the night outdoors or in a public place because you lack a permanent ho

6.verbintransitiveB2
Definition

to spend the night outdoors or in a public place because you lack a permanent home.

Example

After losing his job and his flat, Ziad had to sleep rough for several weeks.

sleep rough (BrE)

The charity provides hot meals for people who are sleeping rough in the city centre.

Common collocations
  • sleep rough
  • sleeping rough
  • people sleeping rough
Synonyms
Antonyms

Grammar Patterns

sleep rough

sleep on the streets

Usage Note

Primarily British English. The equivalent American expression is 'sleep on the streets' or 'sleep outside'. The adjective 'rough' follows the verb directly and cannot be moved.

7. a warm, informal expression said to a person who is heading to bed, wishing them

7.verbintransitiveA2
Definition

a warm, informal expression said to a person who is heading to bed, wishing them a comfortable and restful night.

Example

Liang kissed his daughter on the forehead and said, 'Sleep tight, little one.'

imperative: sleep tight

Before closing the bedroom door, Daniel whispered, 'Sleep well, everyone.'

Common collocations
  • sleep tight
  • sleep well
  • sleep tight, don't let the bedbugs bite
Synonyms
  • sleep well

    more neutral; expresses the same wish without the informal rhyme association

  • sweet dreams

    focuses on dreaming rather than the quality of sleep itself

Grammar Patterns

Sleep tight!

Sleep well!

Usage Note

Almost always used as an imperative or a wish, not in past tense. 'Sleep tight' is often paired with 'don't let the bedbugs bite' as a playful, traditional rhyme. 'Sleep well' is a more neutral alternative.

Phrasal verbs

sleep in

phrasal verb

to sleep later than usual in the morning, especially by staying in bed longer than normal.

On Saturdays, Christopher likes to sleep in until ten o'clock.

The children slept in on New Year's Day after staying up late the night before.

sleep over

phrasal verb

to spend the night at someone else's house, usually as a social visit or for a party.

Adina asked her parents if she could sleep over at Yasmin's house on Friday.

We are planning a movie night — do you want to sleep over?

sleep through

phrasal verb

to continue sleeping without being woken by a noise, event, or activity.

The storm was very loud, but the baby slept through it without making a sound.

Lakan slept through his alarm and arrived at work an hour late.

sleep off

phrasal verb

to get rid of an unpleasant feeling, especially tiredness, illness, or the effects of alcohol, by sleeping.

Joaquín had a bad headache, so he took a nap to sleep it off.

After a long flight, Liang needed a full night to sleep off the jet lag.

to have sex with someone.

The two characters in the novel sleep together early in the story.

Ziad was shocked to learn that his roommate had slept with his ex-girlfriend.

sleep around

phrasal verb

to have sex with many different people in a casual way.

In the film, the main character is known for sleeping around and not having serious relationships.

Some people judge others for sleeping around, but it is a personal choice.

sleep on

phrasal verb

To delay making a decision until the next day after thinking about it overnight.

I'm not sure about the offer; let me sleep on it.

She decided to sleep on the proposal before answering.

sleep together

phrasal verb

To have sex with someone.

They started sleeping together after their third date.

The movie hinted that the couple slept together.

sleep with

phrasal verb

To have sex with someone.

She admitted she slept with her coworker.

He never told anyone he slept with his best friend's sister.

Idioms

to sleep very deeply and heavily, without waking up easily.

After working in the garden all day, Sahil slept like a log and did not hear the thunderstorm.

Esme said she had slept like a log on the new mattress and felt wonderful in the morning.

to not let a problem or worry disturb your rest; to not be overly concerned about something.

It is just a small mistake in the report — do not lose sleep over it.

Marco was angry about the criticism, but he did not lose sleep over it.

to give an animal a drug or injection that causes its death without pain, usually because it is very ill or suffering.

The vet had to put their old dog to sleep because it was in too much pain.

After the cat was diagnosed with a serious illness, the family made the difficult choice to put her to sleep.

To stop worrying and feel calm because a problem is solved or a danger is gone.

After the test, Mia could finally breathe easy.

You can sleep easy now that the report is finished.

To avoid talking about a past problem or argument so that it does not cause trouble now.

I wanted to ask about the fight, but I let sleeping dogs lie.

Why bring up old mistakes? Let sleeping dogs lie.

To sleep outside without a home, usually because you have no money or shelter.

After losing his job, Diego had to sleep rough for a week.

Many people live rough in the city parks during winter.

To stop worrying and feel calm because a problem is solved or a danger is gone.

Now that the storm passed, we can all sleep easy.

Knowing the kids are safe, parents can rest easy.

To sleep very deeply and without waking up.

After hiking all day, Tom slept like a log.

The baby slept like a log through the loud music.

A friendly way to tell someone, especially a child, to sleep well.

Goodnight, Lily. Sleep tight and don't let the bedbugs bite.

Mom kissed me and said, "Sleep tight, sweetie."

sleep — noun

Word family

Synonym discussion

Sense: noun/1

Sleep is the broadest, most neutral term for the natural nightly state of unconscious rest. A nap is a short sleep taken during the day, often for 10–30 minutes, and is usually planned. A doze is a very light, often unintentional sleep — you might doze off while watching TV or reading, and you wake up easily. Snooze is similar to doze but even more informal; it can also refer to hitting the 'snooze' button on an alarm. Slumber is a literary or formal word for deep, peaceful sleep — you are more likely to read 'slumber' in a story than to hear it in conversation. Rest is the broadest of all: it includes sleep but also any period of relaxation or inactivity without necessarily falling asleep. For example, 'I need some rest' could mean you want to lie down, while 'I need some sleep' means you actually want to lose consciousness. When choosing which word to use, consider the length and depth of the sleep: long and deep → sleep or slumber; short and light → doze or snooze; planned short sleep → nap; general relaxation → rest.

sleepnapdozesnoozeslumberrest

Common collocations

Phrases

  • get some sleep
  • lose sleep over
  • put to sleep
  • go to sleep
  • send to sleep

Etymology

Proto-GermanicOld EnglishMiddle EnglishEnglish

The word 'sleep' comes from Old English 'slǣpan' (verb) and 'slǣp' (noun), which belong to the Germanic family of languages. It is related to Old Saxon 'slāpan', Old High German 'slāfan', and Dutch 'slapen'. These forms trace back to a Proto-Germanic root '*slēpaną', meaning 'to sleep'. The word has remained remarkably stable in form and meaning across more than 1,500 years of English history — although the spelling shifted from 'slæpan' to 'sleep' during the Middle English period. The basic concept of sleep as a natural, daily state of rest has not changed, though modern science has added depth to our understanding of its stages and functions.