Longman Dictionary of Contemporary English homepage

Language: Old English
Origin: cnawan

know

1 verb
     
know1 S1 W1 past tense knew past participle known
1

have information

[intransitive,transitive not in progressive] to have information about something:
Who knows the answer?
There are instructions telling you everything you need to know.
Didn't you know that?
know what/how/where etc
Do you know what time it is?
I don't know where to go.
know (something/nothing etc) about something
I need to know more about the job before I decide whether to apply for it.
Little is known about the author's childhood.
I know all about David and what he's been up to!
know (something/nothing etc) of something
I wonder if he knew of the plan?
Do you know of any good restaurants in the area?
You know nothing of this business.
know (that)
We know that greenhouse gases can affect the climate.
Let me know (=tell me) what time you're planning to arrive.
I thought you'd want to know immediately.
If you must know, I was with James last night (=used when you are angry because someone wants to know something).
He slipped out of the house without his parents knowing (=secretly).
How did he know (=how did he find information about) our names?
as you/we know
'I'm divorced, as you know,' she said briefly.
be known to do something
Smoking is known to increase a person's risk of developing lung cancer.
➔ see usage note ignore
2

be sure

[intransitive,transitive not in progressive] to be sure about something:
'Are you seeing Jim tomorrow?' 'I don't know yet.'
know (that)
I know I won't get the job.
Ruth knew that she couldn't continue in the relationship for much longer.
know what/why/how etc
I know exactly what you need!
know if/whether
The boy stared at him uncertainly, not knowing whether to believe him.
I don't know if I'll be able to come.
knowing (that)
She forced herself to go out, knowing that she would feel more depressed if she stayed at home.
How do you know (=what makes you sure) he won't do it again?
know somebody/something to be something
It's a story that I know to be true.
I think he's still living in Chicago, but I don't know for sure.
As far as I know, they're arriving on Saturday (=used when you think something is true but are not sure).
I doubt I'll win, but you never know (=used when you cannot be sure about something, but something good might happen).
3

be familiar with somebody/something

[transitive not in progressive] to be familiar with a person, place etc:
I've known her for twenty years.
Are you really thinking of leaving Kevin for a guy you barely know?
Do you know the nightclub on the corner of Maine Street?
I don't know him very well.
We're still getting to know each other really.
know somebody from something
I know her from school.
know somebody as something
Many people knew him as a local businessman.
Hepburn is best known for (=people are most likely to be familiar with) her roles in classic films such as 'My Fair Lady'.
The museum outlines the development of the city as we know it today.
Does he know the way to your house (=know how to get there)?
I grew up here; I know the place like the back of my hand (=I know it very well).
I only know her by sight (=I often see her but have not really spoken to her).
She didn't know me from Adam, but she was really helpful (=she did not know me at all).
knowing somebody/if I know somebody (=used to say that you expect someone to behave in a particular way because you know them well)
Knowing Sumi, my note's probably still in her pocket.
He'll be chatting up the women, if I know Ron!
4

realize

[intransitive and transitive] to realize, find out about, or understand something:
Hardly knowing what he was doing, Nick pulled out a cigarette.
She knew the risks involved.
know (that)
Suddenly she knew that something was terribly wrong.
know how/what/why etc
I didn't know how difficult it would be.
know to do something
She knows not to tell anyone.
(do/if) you know what I mean? (=used to ask if someone has understood you)
It's nice to have a change sometimes. Know what I mean?
'I just felt so tired.' 'Yeah, I know what you mean.' (=I understand, because I have had the same experience)
I should have known it wouldn't be easy.
I might have known (=I am annoyed but not surprised) you would take that attitude.
know exactly/precisely
I know exactly how you feel.
know perfectly well/full well/only too well
He knew full well that what he was doing was dangerous.
somebody will never know/no one will ever know
Just take it, no one will ever know.
'That's not what I mean, and you know it,' he protested.
if I had known/if I'd have known
I wouldn't have come if I'd known you were so busy.
Little did she know (=she did not know) that years later she would have her own pool and luxury apartment in Florida.
She knew nothing of what had happened earlier that day.
5

skill/experience

[transitive not in progressive] to have learned a lot about something or be skilful and experienced at doing something:
I don't know enough history to make a comparison.
I taught him everything he knows.
I know some French.
know how to do something
Do you know how to change a fuse?
know about
I have a friend who knows about antiques.
Bessie knew nothing about football.
Politicians know all about the power of language.
I don't know the first thing about (=I know nothing about) looking after children.
I don't really know what I'm doing (=I do not have enough skill and experience to deal with something) when it comes to cars.
The staff are dedicated people who clearly know what they are talking about.
She knew from experience that exams made her very nervous.
know your job/subject/stuff (=be good at and know all you should about a job or subject)
a decent manager who knows the ropes (=has a lot of experience)
My cousin knows a thing or two (=know a lot about) about golf.
know a song/tune/poem etc (=be able to sing a song, say a poem etc because you have learned it)
Do you know all the words to 'As Time Goes By'?
6

know somebody's qualities

[transitive not in progressive] to think that someone has particular qualities
know somebody as something
I knew him as a hard-working, modest, and honest politician.
know somebody for something
In fact, I knew her for a tough-minded young woman.
7

know better

a) to be wise or experienced enough not to do something:
It's just prejudice from educated people who should know better.
Eva knew better than to interrupt one of Mark's jokes.
b) to know or think you know more than someone else:
Everyone thought it was an accident. Only Dan knew better.
8

not know any better

used to say that someone does something bad or stupid because they have not been told or taught that it is wrong:
Drugs are being sold to children who don't know any better.
9

know something inside out

also know something backwards British English know something backwards and forwards American English to be very familiar with something, especially because you have learned about it or because you have a lot of experience:
Erikson know the game inside out.
10

know your way around something

a) to be so familiar with something that you are confident and good at using it:
She knows her way around a wine list.
b) to be familiar with a place so that you know where things are:
I don't know my way around the city yet.
11

make yourself known (to somebody)

formal to introduce yourself to someone:
After she had gone, Paul made himself known to Dr Heatherton.
12

recognize

[transitive] to be able to recognize someone or something:
Honestly, it had been so long, I hardly knew her.
know somebody/something by something
He looked very different, but I knew him by his voice.
13

know somebody/something as something

to have a particular name:
The main street between the castle and the palace is known as 'the Royal Mile'.
Nitrous oxide is commonly known as laughing gas.
14

know something from something

to understand the difference between one thing and another:
Lloyd doesn't even know his right from his left.
At what age do children start to know right from wrong?
15

experience

[transitive] to have experience of a particular feeling or situation:
I don't think he ever knew true happiness.
know about
I know all about being poor.
I've never known (=have never experienced) this to happen in all the time I've worked here.
I've never known him to shout (=he never shouts).
16

somebody/something is not known to be something

or somebody/something has never been known to do something used to say there is no information that someone or something has particular qualities:
This species is not known to be vicious.
17

I've known somebody/something to do something

or somebody/something has been known to do something used to say that someone does something sometimes or that something happens sometimes, even if it is unusual:
People have been known to drive 500 miles just to visit the shop.
This type of fish has been known to live for 10 years or more.
18 spoken

you know

a) used to emphasize a statement:
There's no excuse, you know.
b) used to make sure that someone understands what you are saying:
I felt very upset, you know?
c) used when you want to keep someone's attention, but cannot think of what to say next:
Well, you know, we've got a job to do here.
d) used when you are explaining or describing something and want to give more information:
That flower in the garden, you know, the purple one, what is it?
19 spoken

you know/do you know

used to start talking about something, or make someone listen:
You know, I sometimes feel I don't know him at all.
Do you know, when I went out this morning that man was still there.
(do) you know what/something?
You know what? I think he's lonely.
20 spoken

I know

a) used to agree with someone or to say that you feel the same way:
'We have to talk about it, Rob.' 'Yeah, I know.'
b) used to say that you have suddenly had an idea, thought of a solution to a problem, etc:
I know, let's go out for a meal on your birthday.
c) used to stop someone from interrupting because they have an opinion about what you are saying:
It sounds silly, I know, but I will explain.
I know, I know, I should have had the car checked out before now.
21 spoken

I don't know

a) used to say that you do not have the answer to a question:
'When did they arrive?' 'I don't know.'
b) used when you are not sure about something:
'How old do you think he is?' 'Oh, I don't know, sixty, seventy?'
I don't know what/how/whether etc
I don't know whether to call him.
I don't know that
I don't know that you need a passport for travelling within the EU.
c) used to show that you disagree slightly with what has just been said:
'I couldn't live there.' 'Oh, I don't know. It might not be so bad.'
d) British English used to show that you are slightly annoyed:
Oh, I don't know! You're hopeless!
22 spoken

I don't know how/why etc

used to criticize someone:
I don't know how people could keep an animal in those conditions.
23 spoken

I don't know about you but...

used to give your opinion, decision, or suggestion when you are not sure that the person you are talking to will feel the same way:
I don't know about you, but I'll be glad when Christmas is over.
24 spoken

I don't know how to thank you/repay you

used to thank someone
25 spoken

wouldn't you know (it)

used to say that something is not at all surprising:
I was told in no uncertain terms that Helen, wouldn't you know it, didn't approve.
26 spoken

you don't know

used to emphasize how strong your feelings are:
You don't know how much I missed him.
27 spoken

I wouldn't know

used to say that you do not know the answer to something and that you are not the person who would know
28 spoken

what does somebody know?

used to say angrily that someone's opinion is wrong or that it is not important:
What does she know about relationships?
29 spoken

how should I know?/how am I to know?/how do I know?

used to say that it is not reasonable to expect that you should know something:
'When will they be back?' 'How should I know?'
30 spoken

how was I to know?/how did I know?

used as an excuse when something bad has happened:
How was I to know that the file was confidential?
31 spoken

be not to know

British English used to say that you do not mind that someone has made a mistake because they could not have avoided it:
'Sorry, I didn't realize you had guests.' 'That's all right, you weren't to know.'
32 spoken

I ought to know

used to emphasize that you know about something because you made it, experienced it etc:
'Are you sure there's no sugar in this coffee?' 'Of course. I ought to know, I made it!'
33 spoken

for all I know

used to emphasize that you do not know something and say that it is not important to you:
I don't know where she is. She could have been kidnapped for all I know.
34 spoken

not that I know of

used to say that you think the answer is 'no' but there may be facts that you do not know about:
'Did he call earlier?' 'Not that I know of.'
35 spoken

Heaven/God/who/goodness knows!

a) used to say that you do not know the answer to a question:
'Where do you think he's disappeared to this time?' 'God knows!'
Goodness knows why she didn't go herself.
b) used to emphasize a statement:
Goodness knows, I've never liked the woman, but I didn't know how bad it would be to work with her.
36 spoken

knowing my luck

used to say that you expect something bad will happen because you are usually unlucky:
Knowing my luck, the train will be late.
37 spoken

(well,) what do you know?

used to express surprise:
Well, what do you know? Look who's here!
38 spoken

if you know what's good for you

used to tell someone that they should do something, or something bad will happen:
You'll keep your mouth shut about this if you know what's good for you!
39 spoken

you know who/what

used to talk about someone or something without mentioning their name:
I saw you know who yesterday.
40

there's no knowing

it is impossible to know:
There was no knowing who might have read the letter.
41

let it be known/make it known (that)

formal to make sure that people know something, especially by getting someone else to tell them:
Farrar let it be known that he saw nothing wrong with the proposed solutions.
42

not want to know

British English informal to not be interested in someone and what they want to say:
She'd approached several model agencies but they just didn't want to know.
43

know the score

informal to understand a situation and all the good and bad features about it:
I knew the score before I started the job.
44

not know what hit you

informal to feel shocked and confused because something happens when you were not expecting it to:
Poor man, I don't think he knew what hit him.
45

know your place

used to say that someone understands that they are less important than other people - usually used humorously:
I know my place. I'll get back to the kitchen!
46

know no bounds

formal if a feeling or quality knows no bounds, it is not limited in any way:
His enthusiasm knew no bounds.
47

somebody knows best

used to say that someone should be obeyed or that their way of doing things should be accepted because they are experienced:
She always thinks she knows best.
I have always hated the attitude that 'the doctor knows best'.
48

before you know it

used to say that something happens very quickly and when you are not expecting it:
You'll be home before you know it.
49

know different/otherwise

informal to know that the opposite of something is true:
He told people he didn't care about her, but deep down he knew different.
50

know your own mind

to be confident and have firm ideas about what you want and like
51

you will be delighted/pleased etc to know (that)

formal used before you give someone information that they will be pleased to hear:
You will be pleased to know that we have accepted your offer.
52

it's ... Jim, but not as we know it

informal humorous used to say that something is completely different from what we would normally expect something of its type to be:
It's the blues Jim, but not as we know it.

➔ the next thing I/she etc knew

at next1 (6)WORD CHOICE: WORD CHOICE:

know, find out, get to knowKnow means to have information about something • I know where you live. • I never knew you were such a good dancer.!! Do not use know when you mean to get information about something that you want to know. Use find out instead • I went to the window to find out what was happening outside (NOT I went to the window to know what was happening outside).Know also means to be familiar with someone or something • Do you know Sara well? • I don't really know London.!! Do not use know when you mean become familiar with someone or something. Use get to know instead • I'd like to get to know her better (NOT I'd like to know her better). • The best way to get to know Venice is by boat (NOT The best way to know Venice is by boat.)
Definition from the Longman Dictionary of Contemporary English
Advanced Learner's Dictionary.
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