semafor Englisch:

They dubbed their invention the “telegraph,” though nowadays all the early visual transmission systems are referred to as optical telegraphs, and this particular version is called a semaphore telegraph.

The ship's captain ordered the radio operator to send a distress signal.

The radio station broadcasts a very strong signal.

An increase in customer complaints could signal a decline in business.

It's dangerous to ignore the signal at a railroad crossing.

I will give a signal and we will sing "Happy birthday".

Catch a signal.

Many Americans are uncomfortable with silence, and they tend to regard silence in a conversation as a signal that they need to start talking.

A display, aka monitor, is an appliance that displays video signal of still images and moving pictures produced by a computer or similar device.

On my signal both teams run into the river.

Everybody made for the door at the signal.

The signal at the intersection didn't increase the number of the traffic accidents in the city.

The fireworks were a signal that the celebration had started.

I have no signal. I can't make a call.

Animals show their teeth to signal that they are angry.

We lit a fire as a signal for any passing ships or planes to find us.