Cambridge Dictionaries online Cambridge Dictionaries online

The most popular online dictionary and thesaurus for learners of English

English definition of “know”

know

verb   /nəʊ/ (knew, known)
A1 to have information about something in your mind: “How old is she?” “I don’t know.” He knew that she was lying.
A1 used to ask someone to tell you a piece of information: Do you know where the post office is?
A2 to be certain: I know she’ll be really pleased to hear the news.
A2 to be able to do something: Do you know how to ski?
B1 to have spent time with someone or in a place so that the person or place is not new to you: I’ve known Al since we were children. I grew up in Brussels so I know it well.
let someone know A2 to tell someone something: Let me know if you’re going to the party.
I know used when you agree with something someone has just said: “It’s a lovely day, isn’t it?” “I know – let’s hope it lasts.”
you know B1 used to make sure someone understands which person or thing you are talking about: I was talking about Rachel – you know, the tall woman with the blond hair.
B1 (also know about) If you know a subject, or you know about it, you are familiar with it and understand it: Ask Andy to fix it – he knows about computers.
be known as something B1 to be called: California is also known as the Sunshine State.
get to know someone/something B1 to gradually learn more about someone or something: I got to know Frank at work.
as far as I know used to say that you think something is true, but cannot be sure: As far as I know, he isn’t married.
(Definition of know verb from the Cambridge Essential Dictionary © Cambridge University Press)

More Essential British English definitions for “know”

Definitions of “know” in other dictionaries

Word of the Day

handout

a document given to students or reporters which contains information about a particular subject

Word of the Day

Blog

Read our blog about how the English language behaves.

Learn More

New Words

Find words and meanings that have just started to be used in English, and let us know what you think of them.

Learn More