key · noun C /kiː/Full view
key (FOR LOCKS)
A1 a piece of metal cut into a particular shape that is used for opening or closing the lock of a door, starting a car engine, etc.
Dictionary example:

car/door/house keys

Learner example:

I left my keys at your house. (Key English Test; A2; Slovak)

key (ANSWERS)
A2 a list of answers to an exercise, quiz, test, etc.
Dictionary example:

You can check your answers in the answer key on page 176.

key (METHOD)
B1 a way of explaining or achieving something
Dictionary example:

Hard work is the key to success.

Learner example:

To those who say that money can't buy happiness I answer that money is a key to happiness. (First Certificate in English; B2; French)

key (KEYBOARD)
B2 one of the places that you press with your fingers on a device such as a computer or on a musical instrument to produce letters, numbers, symbols, or produce a sound
Dictionary examples:

Press the shift key to write in capital letters.

piano keys

Learner example:

What is more, you can get the information you need in just one second by pressing the "enter" key [o]n a computer. (First Certificate in English; B2; Spanish)

key · adjective /kiː/
key
B2 very important in influencing or achieving something
Dictionary examples:

She was a key figure in the international art world.

a key factor in tackling the problem

Learner example:

Unfortunately one day I decided that it was time to become more independent and I didn't ask a key question. (First Certificate in English; B2; Polish)

be key to sth
C1 to be very important in influencing or achieving something
Dictionary example:

Early diagnosis is key to your chances of surviving.

Learner example:

Distribution is key to achiev[ing] economic growth and the positioning of domestic and imported goods. (International English Language Testing System; C1; Spanish)

key · verb /kiː/

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