1. [Usually made with mouth movement] a device for making sounds louder, especially a person's voice, or to record them on a tape recorder. English = microphone.
2. A person whose job involves using a microphone to announce things or to record news for radio or television. English = announcer, radio journalist, television journalist.
3. An amplified message played at a public place, such as a railway station, airport, shopping centre. English = announcement.