amplifier

American  

[am-pluh-fahy-er] / ˈæm pləˌfaɪ ər /

noun

1. a person or thing that amplifies or enlarges.

2. an electronic component or circuit for amplifying power, current, or voltage.

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amplifier British  

/ ˈæmplɪˌfaɪə /

noun

1. an electronic device used to increase the strength of the signal fed into it

2. such a device used for the amplification of audio frequency signals in a radio, etc

3. photog an additional lens for altering the focal length of a camera lens

4. a person or thing that amplifies

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amplifier Cultural  

1. In electronics, a device that takes a small electric signal and converts it into a large one. Amplifiers are used in stereo systems, electric guitars, and loudspeakers.

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Etymology

Origin of amplifier

First recorded in 1540–50; amplify + -er ¹

Compare meaning

How does amplifier compare to similar and commonly confused words? Explore the most common comparisons:

• preamplifier vs. amplifier

Explanation

An amplifier is a device that makes an electronic signal stronger, and it's most often used to increase the volume of musical instruments. If you play electric guitar in a rock band, you use an amplifier. In scientific terms, an amplifier can increase (or amplify) any type of signal, including magnetic signals and optical signals. When people talk about amplifiers, they usually mean the ones used by musicians and sound engineers. If you plug your electric bass guitar into an amplifier, you can make the sound loud enough that your next door neighbors will be able to hear it. You can call an amplifier an amp for short.

Example Sentences

In principle, such a plasma can act as an energy amplifier, producing far more energy than it takes to create and sustain it.

From The Wall Street Journal • Dec. 28, 2025

He learned to beatmatch by plugging a player into each side of his amplifier and using the balance knob to fade between them.

From Los Angeles Times • Dec. 17, 2025

Conventional signals are refreshed roughly every 50 kilometers using an optical amplifier.

From Science Daily • Nov. 29, 2025

For many people with chronic pain, the metaphors that scientists use—like the amplifier, making a whisper sound like a scream—don’t tell the whole story.

From Slate • Sep. 15, 2025

But alive, he was invaluable to their mission, trained to use his amplifier gifts to sense Grisha power through touch.

From "Six of Crows" by Leigh Bardugo