Here is a list of idiomatic expressions about mouse. Each idiom is followed by its meaning or definition.

As poor as a church mouse

If somebody is as poor as a church mouse, they are very poor.

• My father was as poor as a church mouse and couldn’t afford to give us good education.

As quiet as a mouse

If you are as quiet as a mouse, you are very quiet or shy.

• When she was a child, she was as quiet as a mouse.

The best-laid plans of mice and men

This expression is used to refer to the most thoughtful plans that you can make.

• Even the best-laid plans of mice and men won’t solve my problems.

Play cat and mouse with (someone)

To play cat and mouse with somebody is to fool them or to change between different kinds of behavior.

• He must stop playing cat and mouse with her.

When the cat’s away, the mice will play

This expression is used to mean that someone will do something mischievous if you do not watch them.

• I never leave my boys unattended. When the cat is away, the mice will play.