1 [with clause] be aware of through observation, inquiry, or information:most people know that CFCs can damage the ozone layerI know what I’m doing
[with object] have knowledge or information concerning:I would write to him if I knew his address [no object]:I know of one local who shot himself
be absolutely certain or sure about something:I just knew it was something I wanted to do [with object]:I knew it!
2 [with object] have developed a relationship with (someone) through meeting and spending time with them; be familiar or friendly with:he knew and respected Laura
have a good command of (a subject or language).
recognize (someone or something):Isabel couldn’t hear the words clearly but she knew the voice
be familiar or acquainted with (something):a little restaurant she knew near Leicester Square
have personal experience of (an emotion or situation):a man who had known better times
(usually be known as) regard or perceive as having a specified characteristic:the loch is known as a dangerous area for swimming
(usually be known as) give (someone or something) a particular name or title:the doctor was universally known as ‘Hubert’
(know someone/thing from) be able to distinguish one person or thing from (another):you are convinced you know your own baby from any other in the world
3 [with object] archaic have sexual intercourse with (someone).
[a Hebraism which has passed into modern languages; compare with German erkennen, French connaître]
and one knows it
said to emphasize that someone is well aware of a fact although they might pretend otherwise:that’s nonsense and you know it
—— as we know it
as is familiar or customary in the present:apocalyptic expectations, envisaging the end of the world as we know it
before one knows where one is (or before one knows it)
informal with baffling speed.
be in the know
be aware of something known only to a few people:he had a tip from a friend in the know: the horse was a cert
be not to know
have no way of being aware of:you weren’t to know he was about to die
don't I know it!
informal used as an expression of rueful assent or agreement.
don't you know
informal, dated used to emphasize what one has just said or is about to say:I was, don’t you know, a great motoring enthusiast in those days
for all someone knows
used to express the limited scope or extent of one’s information:she could be dead for all I know
God (or goodness or heaven) knows
1used to emphasize that one does not know something:God knows what else they might find
2used to emphasize the truth of a statement:goodness knows, I haven’t been perfect
have been known to do something
have occasionally in the past done something:the fans have been known to rain bottles, cans, and seats on players who displease them
I know
1I agree:‘It’s not the same without Rosie.’ ‘I know.’
2 (also I know what) I have a new idea or suggestion:I know what, let’s do it now
have better knowledge or more appropriate skills:a mother always knows best where her children are concerned
know better than
be wise or polite enough to avoid doing a particular thing:you ought to know better than to ask that
know someone by sight
recognize someone by their appearance without knowing their name or being so well acquainted as to talk to them.
know different (or otherwise)
be aware of information or evidence to the contrary.
know something for a fact
be aware of something that is irrefutable or beyond doubt:I know for a fact that he can’t speak a word of Japanese
know someone in the biblical sense
informal, humorous have sexual intercourse with someone.
know no bounds
have no limits:their courage knows no bounds
know one's own mind
be decisive and certain.
know one's way around (or about)
be familiar with (an area, procedure, or subject).
know the ropes
have experience of the appropriate procedures.
[with reference to ropes used in sailing]
know what one likes
have fixed or definite tastes, without necessarily having the knowledge or informed opinion to support them:I don’t understand all this modern poetry at all, but I know what I like
know what's what
informal be experienced and competent in a particular area.
know who's who
be aware of the identity and status of each person.
let it be (or make something) known
ensure that people are informed about something, especially via a third party: [with clause]:the Minister let it be known that he was not seeking reappointment
not know from nothing
North American informal be totally ignorant:she shakes her head while you talk, as if to say you don’t know from nothing
not know the first thing about
have not the slightest idea about (something):he’s an engineer, doesn’t know the first thing about literature
not know that
informal used to express one’s doubts about one’s ability to do something:I don’t know that I can sum up my meaning on paper
not know what hit one
be very shocked or surprised by a sudden attack or event.
not know what to do with oneself
be at a loss as to know what to do, typically through boredom, embarrassment, or anxiety.
not know where (or which way) to look
feel great embarrassment and not know how to react.
not want to know
informal refuse to react or take notice:they just didn’t want to know when I gave my side of the story
what does —— know?
informal used to indicate that someone knows nothing about the subject in question:what does he know about football, anyway?
what do you know (about that)?
North American informal used as an expression of surprise.
wouldn't you like to know?
informal used to express one’s intention to keep something secret despite another’s curiosity:‘You’re loaded, aren’t you, Bella?’ ‘Wouldn’t you like to know?’
you know
informal
used to indicate that what is being referred to is known to or understood by the listener:when in Rome, you know
used as a filler in conversation:oh well, you know, I was wondering if you had any jobs for me
you know something (or what)?
informal used to indicate that one is going to say something interesting or surprising:You know what? I believed her
