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under lock and key

This page is about the idiom under lock and key


If something is under lock and key, it is kept in a very secure place.

For example

  • Make sure these documents are under lock and key until we need them.

  • Poor Josie. Her parents were very strict and they kept her under lock and key throughout her childhood, so she never learned about life's dangers.

Quick Quiz

The medicines are kept under lock and key so that

a. they can't be used

b. we can get them quickly

c. the children can't get them

Idiom of the Day

Contributor: Matt Errey