French horn and Speaking trumpet

French horn noun - A brass musical instrument consisting of a conical tube that is coiled into a spiral and played by means of valves.

Speaking trumpet and French horn are semantically related in trumpet topic. In some cases you can use "Speaking trumpet" instead a noun phrase "French horn".

Speaking trumpet noun - A trumpet-shaped acoustic device to intensify and direct the human voice; formerly held to the ear by a hard-of-hearing person.

French horn and speaking trumpet are semantically related in trumpet topic. You can use "French horn" instead a noun phrase "Speaking trumpet".