know

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verb [never progressive] British English pronunciation: know

/nəʊ/

present tense
I/you/we/they	know
he/she/it	knows
present participle	knowing
past tense	knew
past participle	known

See also
Expressing yourself

1
[intransitive/transitive] to have learned or found out about something
‘Have they arrived yet?’ ‘I don’t know.’
If you don’t know the answer, just guess.
How do you know my name?
know (that):
I knew she wasn’t really happy.
know what/where/how etc:
I don’t know where the money’s coming from.
know if:
I need to know if she’s made a decision yet.
know something about someone/something:
I don’t know anything about it.
know something for sure/for certain/for a fact:
We know for a fact that the fire was started deliberately.
know something from experience:
We know from experience that unemployment makes the problem worse.
Thesaurus entry for this meaning of know
1. a.
  [intransitive/transitive] to realize or understand something
  None of us really knew what had gone wrong.
  Thesaurus entry for this meaning of know
2. b.
  [transitive] [often passive] used about things that most people think or believe are true
  The ancient city is known to have existed in the region.
  know someone/something to be something:
  The pilots were experienced and known to be very competent.
  know someone/something to do something:
  Some drugs are known to cause damage to unborn children.
  Thesaurus entry for this meaning of know
2
[transitive] to be familiar with someone, because you have met them or because you are friends
Some of you may know Ivan already.
I felt I hardly knew my father.
She had known Nancy for years.
Thesaurus entry for this meaning of know
1. a.
  to be familiar with a place, because you have been there
  Do you know Rome well?
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2. b.
  to be familiar with things such as books, music, or art
  Do you know Beethoven’s Ninth Symphony?
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3. c.
  to be familiar with a process or system
  Do you know this program?
  You know the rules.
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4. d.
  to be able to speak a language
  Do you know any Spanish?
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3
[transitive] to use a particular name for someone or something
know someone/something as something:
The village was known as Garden Mill.
know someone/something by something:
They know all their tutors by their first names.
Thesaurus entry for this meaning of know
4
[transitive] to remember or recognize someone because of a particular skill or quality that they have
know someone as/for something:
He was best known as a painter.
We know her mostly for her love poetry.
Thesaurus entry for this meaning of know
5
[transitive] to experience something
It was the only comfort and warmth she had ever known.
have never known someone (to) do something:
I’ve never known her to make a joke.
Thesaurus entry for this meaning of know
6
[transitive] to have learned a poem, story, or song, so that you can say it or sing it
I still know the words to some of these hymns.
Thesaurus entry for this meaning of know
7
[intransitive/transitive] to feel certain about something
know (that):
She knew it was Steven before she’d picked up the phone.
Thesaurus entry for this meaning of know
8
[transitive] to recognize someone or something
It was Henry: I would have known him anywhere.
Thesaurus entry for this meaning of know

phrases

as we know it
used when you are talking about something that people are familiar with, especially something that is likely to change
This could mean the end of life as we know it.
Thesaurus entry for this meaning of know
as you know
mainly spoken
used when you are saying something that someone already knows
As you know, we’ve already accepted an offer from another company.
Thesaurus entry for this meaning of know
for all I know
used for emphasizing that you do not know something
He could be a murderer for all I know.
Thesaurus entry for this meaning of know
get to know
to start to be familiar with someone or something
It took a while to get to know the city properly.
Thesaurus entry for this meaning of know
God/Goodness/Heaven knows
mainly spoken
1. 1
  used for emphasis
  God knows, it would be a disaster if that happened.
  Thesaurus entry for this meaning of know
2. 2
  used for saying that you do not know something
  ‘Where on earth can they have got to?’ ‘Goodness knows.’
  What effect it will have, heaven only knows.
  Thesaurus entry for this meaning of know
how should/do I know?
spoken
used for saying in an annoyed way that you do not know something
How should I know what she thinks about it?
Thesaurus entry for this meaning of know
I don’t know
1. 1
  used for saying that you are not certain about something
  I don’t know whether:
  I don’t know whether economic issues were discussed specifically.
  Thesaurus entry for this meaning of know
2. 2
  used for saying that you do not completely agree
  ‘It’ll be boring.’ ‘Oh I don’t know. It might be fun.’
  I don’t know that:
  I don’t know that we need to discuss this.
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3. 3
  used when you are giving your opinion and want to find out what someone else thinks
  I don’t know about you, but I’m starving.
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4. 4
  used for criticizing someone
  I don’t know what/how/why etc:
  I don’t know what they were thinking of.
  I don’t know how he could be so cruel.
  Thesaurus entry for this meaning of know
if you must know
spoken
used for answering someone in an annoyed way
He’s not my boyfriend any more, if you must know.
Thesaurus entry for this meaning of know
I know
1. 1
  used for agreeing with what someone says
  ‘He’s a complete idiot.’ ‘Yeah, I know.’
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2. 2
  used for showing that you know there is a problem, but you do not think it is important
  I know the plan is pretty rough, but you get the idea.
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3. 3
  used for showing that you understand someone and feel sympathy for them
  I know how hard this is for you.
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4. 4
  used when you have a sudden idea
  I know, let’s go to the cinema instead.
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know something backwards/inside out
to be very familiar with something
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know best
used for saying whose opinion is most important
When it comes to toys, your child knows best.
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know better
1. 1
  used for saying that someone should not make a mistake, because they are sensible or experienced
  She should know better than to try to fool him.
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2. 2
  to know that what someone else says or thinks is wrong
  Everyone thought it was an innocent mistake, but I knew better.
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know your own mind
to be certain about what you like and what you want
Michael is a man who knows his own mind and I was expecting him to be critical.
Thesaurus entry for this meaning of know
know what’s what
spoken
to be very clever or experienced
Thesaurus entry for this meaning of know
let someone know
to tell someone something
Let me know when he arrives.
Thesaurus entry for this meaning of know
not know whether you are coming or going
spoken
to feel very confused, for example because you are very busy
I’m so tired, I don’t know whether I’m coming or going.
Thesaurus entry for this meaning of know
not want to know
informal
to refuse to listen to someone or get involved in something
We asked several of them to help, but they didn’t want to know.
Thesaurus entry for this meaning of know
what do you know
spoken
used for showing that you are surprised
Thesaurus entry for this meaning of know
you don’t know
spoken
used for emphasizing what you are going to say next
You don’t know how happy this makes me!
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you know
spoken
1. 1
  used for emphasis
  Things are different now, you know.
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2. 2
  informal used while you think about what to say next
  My whole leg was, you know, soaked in blood.
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3. 3
  used when you are giving extra information about something
  Have you seen that bowl, you know, the blue one?
  Thesaurus entry for this meaning of know
4. 4
  used before you start to talk about a particular person or thing
  You know the woman next door? Well, she’s expecting a baby.
  Thesaurus entry for this meaning of know

phrasal verbs

showmance

a romantic relationship between two members of the cast of a play, film or television series

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human-readable

able to be read and understood by people

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Related dictionary definitions

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phrases

as we know it

as you know

for all I know

get to know

God/Goodness/Heaven knows

how should/do I know?

I don’t know

if you must know

I know

know something backwards/inside out

know best

know better

know your own mind

know what’s what

let someone know

not know whether you are coming or going

not want to know

what do you know

you don’t know

you know

phrasal verbs

showmance

Word of the Day

pumice

human-readable