transmitter

American  

[trans-mit-er, tranz-] / trænsˈmɪt ər, trænz- /

noun

1. a person or thing that transmits.

2. Also called transmitting set.  Radio. a device for sending electromagnetic waves; the part of a broadcasting apparatus that generates and modulates the radiofrequency current and conveys it to the antenna.

3. the part of a telephonic or telegraphic apparatus that converts sound waves or mechanical movements into corresponding electric waves or impulses.

4. Biochemistry. neurotransmitter.

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transmitter British  

/ trænzˈmɪtə /

noun

1. a person or thing that transmits

2. the equipment used for generating and amplifying a radio-frequency carrier, modulating the carrier with information, and feeding it to an aerial for transmission

3. the microphone in a telephone that converts sound waves into audio-frequency electrical signals

4. a device that converts mechanical movements into coded electrical signals transmitted along a telegraph circuit

5. physiol short for neurotransmitter

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transmitter Scientific  

/ trăns′mĭt-ər /

1. A device that converts sound, light, or electrical signals into radio, microwave, or other electrical signals of sufficient strength for the purpose of telecommunication.

2. Compare receiver

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Etymology

Origin of transmitter

First recorded in 1720–30; transmit + -er ¹

Example Sentences

All one needs is "another radio transmitter that can broadcast on the same frequency, but louder," she said, which creates "a wall of mush."

From Barron's • Mar. 8, 2026

Also benefitting are the University of Strathclyde, to develop a satellite navigation system that doesn't rely on GPS, and Heriot-Watt University to help build a quantum communication transmitter for small satellites.

From BBC • Dec. 3, 2025

And to a $400 satellite transmitter, called an InReach, that she used to send an SOS message and communicate with authorities despite the lack of a cellphone signal.

From Los Angeles Times • Jul. 8, 2025

While no longer resembling a bulky transmitter, the basic hearing-aid concept is the same as when I was in high school 50 years ago.

From Salon • Sep. 30, 2024

Bigger saw Gus cup his left hand to his ear, as though holding a telephone receiver; and cup his right hand to his mouth, as though talking into a transmitter.

From "Native Son" by Richard Wright