Get on the horn and Pick up

Pick up and get on the horn are semantically related. in telephone topic. In some cases you can use "Pick up" instead a verb phrase "Get on the horn", when it comes to topics like communicate through telephone system.

Pick up verb - To acquire complete knowledge, understanding, or skill in.

Get on the horn and pick up are semantically related. Sometimes you can use "Get on the horn" instead a verb "Pick up".