- noun a person who sends something, especially a letter
- A component, device, piece of equipment, system, object, or entity which emits, radiates, or otherwise sends signals. Transmitters which send information-bearing signals are used in many areas, including communications, TV and entertainment, radars, and so on. Also called transmitter (1).
- A circuit, device, or system which converts audio, video, or other content into radio waves which are emitted. AM, FM, and AM/FM transmitters are examples. Also called transmitter (2), radio transmitter, or radio sender.
- noun in a piece of communication, the person who is transmitting the message