鍵
Meanings
1
Physical key for a lock. Also used metaphorically for something that provides access or a solution.
I forgot my house key.
Where is the key to this box?
2
Refers to the locking mechanism itself, often used in contexts like 鍵をかける (to lock).
See also: 錠
Please lock the door.
3
key (to a problem, success, etc.); clue
Figurative use: the crucial element for solving a problem or achieving something.
The key to success is hard work.
A person who holds the key to the case.
Usage patterns
- 〈場所〉の鍵を開けるto unlock (a door, room, etc.) with a key
He unlocked the room and went inside.
- 鍵をなくすto lose one's key
I ended up losing the key to my house.
- 〈人〉に鍵を渡すto hand someone a/the key
I handed the room key to the building manager.
- 〈事〉の鍵となるto be the key (crucial factor) to something
This technology will be the key to the negotiation's success.