key
/kiː/ · key
noun
- An object designed to open and close a lock. She inserted the key into the lock and turned it.
- An object designed to fit between two other objects (such as a shaft and a wheel) in a mechanism and maintain their relative orientation. The key ensured that the gears meshed properly.
noun
- A crucial step or requirement. The key to solving this problem is persistence.
verb
- To fit (a lock) with a key. She keyed the lock and opened the door.
- To fit (pieces of a mechanical assembly) with a key to maintain the orientation between them. The engineer keyed the gears to ensure proper alignment.
verb
- To mark or indicate with a symbol indicating membership in a class. The teacher keyed the students' grades into the computer.
adjective
- Indispensable, supremely important. He is the key player on his soccer team.
- Important, salient. She makes several key points.
Synonyms
Antonyms
Did you know? The word 'key' has been used in various idiomatic expressions, such as 'key to success' and 'key player', emphasizing the importance of a particular factor or individual in achieving a goal or outcome.