key
/kiː/
noun
-
A small metal or electronic object used to open or lock something, especially a door.
A1countable
- "I can't find my house key."A1
- "The key to the cabinet is on the hook."A2
- "She used a spare key to open the office."B1
-
A button on a computer, phone, or other device that you press to produce a letter, number, or function.
A2countable
- "Press the Enter key."A2
- "The space bar is the longest key on most keyboards."B1
-
A crucial or essential element that is necessary for something to work or be successful.
B1countable
- "The key to success is hard work."B1
- "Understanding the basics is the key to learning a new language."B2
-
The information that explains symbols on a map, chart, or diagram, or the answer to a puzzle.
B1countable
- "Use the key to understand the map."B1
- "The answer key is at the back of the book."B2
adjective
-
Very important or essential, or central to understanding or solving something.
B1attributive
- "Good communication is key to success."B1
- "The key factor in the experiment was temperature."B1
- "Trust is a key element of a successful partnership."B2
verb
-
To operate a lock with a key, especially to lock or unlock something.
A2transitive
- "She keyed the door to enter the house."A2
-
To enter information by pressing keys on a computer or other device.
B2transitive; often key in
- "Please key in your password."B2
- "The receptionist keyed the customer details into the system."C1
-
To damage a vehicle or other surface by scratching it with a key.
B2transitiveinformal
- "Someone keyed my car last night."B2
- "The parked car had been deliberately keyed along one side."C1
Common mistakes
- the key of success→the key to success
Use key to when describing something that helps produce a result.
- keynote→key note
Keynote is a noun meaning the main speech at a conference, while key note means the most important note in a piece of music.