The word toe is used in some common idiomatic expressions. Here is a list of them.

Dip your toe into something

To dip your toe into something is to try doing it in order to test whether you will be able to do it.

By launching their own handset, they have dipped their toe into the lucrative smartphone market.

The expression ‘dip a toe in the water’ means the same.

From head to toe / from top to toe

If a person is covered from head to toe, the whole of their body is covered.

She was covered in black fur from head to toe.

Keep someone on their toes

To keep someone on their toes is to keep them alert.

My little kids keep me on my toes all the time.

Make someone’s toes curl

To make someone’s toes curl is to make them feel extremely embarrassed.

The very thought of that incident makes my toes curl.

Tread/step on someone’s toes

To tread on someone’s toes is to offend them by doing something that they have the authority to do.

You shouldn’t have stepped on your manager’s toes by talking to the media without his consent.

Touch your toes

To touch your toes is to bend while keeping your legs straight. This is a form of physical exercise.