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know

1 know /ˈnoʊ/ verb
knows; knew /ˈnuː/; Brit /ˈnjuː/ ; known /ˈnoʊn/ ; knowing
1 know
/ˈnoʊ/
verb
knows; knew /ˈnuː/; Brit /ˈnjuː/ ; known /ˈnoʊn/ ; knowing
Britannica Dictionary definition of KNOW
not used in progressive tenses
: to have (information of some kind) in your mind
[+ object]
often + how, why, where, etc.
[no object]
often + about
: to understand (something) : to have a clear and complete idea of (something)
[+ object]
usually + how, why, where, etc.
[no object]
[+ object] : to have learned (something, such as a skill or a language) often + how
: to be aware of (something) : to realize (something)
[+ object]
[no object]
often + about or of
: to be certain of (something)
[+ object]
[no object]
[+ object]
: to have met and talked to (someone) : to be acquainted or familiar with (a person)
: to have experience with (something) : to be acquainted or familiar with (something)
: to have experienced (something)
usually used as known
[+ object]
: to recognize (someone or something) : to identify (someone or something) accurately
: to recognize the difference between two things : to be able to distinguish (one thing) from another
[+ object]
: to be sure that (someone or something) has a particular quality, character, etc., because of your experiences with that person or thing usually followed by to + verb
: to think of (someone or something) as having a particular quality, character, etc. + as
often used as (be) known as
used to indicate the name that people know or use for someone or something + as
often used as (be) known as
used to say that someone or something has a particular quality, feature, ability, etc., that people know about + for
usually used as (be) known for
◊ Someone who has been known to be or known to do something has been or done that thing in the past.

before you know it

: very quickly or soon

better the devil you know than the devil you don't

see devil

don't I know it

informal
used to say that you agree with what has just been said

for all I know

informal
used to say that you have little or no knowledge of something

God knows

informal or goodness knows or heaven knows or Lord knows
used to stress that something is not known
used to make a statement more forceful

have known better days

see 1better

I don't know

used to say that you do not have the information someone is asking for
informal used to express disagreement, doubt, or uncertainty
used to say that you are uncertain about someone or something

if you must know

used when you are answering a question that you do not want to answer because the information is personal, embarrassing, etc.

I'll have you know

see have

I know (it)

used to express agreement
used to introduce a suggestion

I wouldn't know

used to say that you have not experienced something

know best

or know what's best
: to know or understand better than someone else what should be done

know better

: to be smart or sensible enough not to do something
: to know or understand the truth about something
: to know or understand more than other people

know different/otherwise

: to know that something that people think or say is true is not really true

know from

[phrasal verb]
know from (someone or something) US, informal
: to know anything about or care at all about (someone or something) used in negative statements

know no boundaries

see boundary

know no bounds

see 6bound

know (something) backward and forward

or British know (something) backwards or know (something) inside out or US know (something) inside and out or know (something) like the back of your hand
: to know something completely

know (something or someone) for what it/he/she is

: to understand what something or someone truly is

know (something) when you see it/one

: to be able to recognize or identify something immediately

know the drill

see 1drill

know the score

see 1score

know what hit you

used in negative statements to say that something you did not expect surprised you very much

know what it is

or to know what it's like
: to have experience with a situation, activity, or condition

know what you are talking about

◊ If you know what you are talking about, you deserve to be listened to because you have actual knowledge or experience with something and what you are saying is correct.

know which side your bread is buttered on

see 1bread

know your own heart/mind

: to be sure of what you want, like, think, etc.

know yourself

: to understand yourself fully : to understand your own emotions, desires, abilities, etc.

know your stuff

see 1stuff

know your way around

◊ If you know your way around a place or thing, you are very familiar with it or are good at using or operating it.

let (someone) know

: to tell something to someone

let (something) be known

formal or make (something) known
: to tell people something

make yourself known

formal
: to introduce yourself : to cause people to know who you are

might/should have known

used to say that you are not surprised to learn of something

not know someone from Adam

informal
: to have never met with someone : to not know someone at all

not know the first thing about

: to have little or no knowledge about (something or someone)

not know the meaning of (the word)

see meaning

not know your ass from your elbow

(chiefly US) informal + impolite or British not know your arse from your elbow
: to know nothing : to be stupid

what do you know

informal
used to express surprise
used to say that someone is wrong about something

wouldn't you know (it)?

informal
used to say that something annoying that has happened is the kind of thing that often happens

you know

informal
used when you are trying to help someone remember something
used for emphasis
used when you are not sure of what to say or how to say it

you know something/what?

informal
used to emphasize the statement that comes after it
used to get someone's attention

you know what I mean

informal
used to suggest that the hearer agrees with and understands what has been said or to ask if he or she does or not
sometimes used in the shortened form know what I mean

you know what they say

informal
used to introduce a common saying or a statement that expresses a common belief

you never know

used to say that it is impossible to be sure about what will happen
2 know /ˈnoʊ/ noun
2 know
/ˈnoʊ/
noun
Britannica Dictionary definition of KNOW

in the know

: having knowledge about something : having information that most people do not have