key definition, meaning - what is key in the British English Dictionary & Thesaurus - Cambridge Dictionaries Online

Cambridge Dictionaries online Cambridge Dictionaries online

The most popular online dictionary and thesaurus for learners of English

English definition of “key”

See all translations

key

noun [C] uk   us   /kiː/

key noun [C] (LOCK)

A1 a piece of metal that has been cut into a special shape and is used for opening or closing a lock, starting a car engine, etc.: car/door keys
More examples

key noun [C] (PART)

B2 any of the set of moving parts that you press with your fingers on a computer keyboard, or musical instrument to produce letters, numbers, symbols, or musical notes
More examples

key noun [C] (MUSICAL NOTES)

a set of musical notes based on one particular note: The song changes key halfway through. the key of C minor

key noun [C] (SYMBOLS)

a list of the symbols used in a map or book with explanations of what they mean

key noun [C] (ANSWERS)

A2 a list of the answers to the questions in an exercise or test: See the key to test 3 on page 176.

key

adjective uk   us   /kiː/
B2 very important and having a lot of influence on other people or things: She was a key figure in the international art world. a key factor in tackling the problem
More examples
(Definition of key from the Cambridge Advanced Learners Dictionary & Thesaurus © Cambridge University Press)
What is the pronunciation of key?
Add Cambridge dictionaries to your browser to your website

Definitions of “key” in other dictionaries

Word of the Day

intellectualize

to think about or discuss a subject in a detailed and intellectual way, without involving your emotions or feelings

Word of the Day

What’s All The Commotion About? (Words to describe sounds)

by Kate Woodford,
May 20, 2015
​​​ In this post we look at a range of words and phrases that we use to describe noise and the absence of noise. Starting with complete quiet, we sometimes use the noun hush to describe silence: A hush fell over the room as the bride walked in./There was a deathly hush (=complete

Read More 

plyscraper noun

May 18, 2015
a skyscraper made mainly from wood The development of engineered timber could herald a new era of eco-friendly ‘plyscrapers’. Christchurch welcomed its first multistorey timber structure this year, there are plans for Vancouver, and the talk is China could follow

Read More