under lock and key
1. Locked up
2. Imprisoned
• • •
Main Entry: ↑lock
* * *
under lock and key phrase
in a room or container which is fastened with a lock
These files should be kept under lock and key.
Main entry: lock
* * *
Isee lock I
II
securely locked up
* * *
• • •
Main Entry: ↑key
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under lock and key
The jewels are kept under lock and key.
The prisoner is being kept/held under lock and key.
• • •
Main Entry: ↑lock
Useful english dictionary. 2012.