hydrophone

American  

[hahy-druh-fohn] / ˈhaɪ drəˌfoʊn /

noun

1. a device for locating sources of sound under water, as for detecting submarines by the noise of their engines.

2. an instrument employing the principles of the microphone, used to detect the flow of water through a pipe.

3. Medicine/Medical. an instrument used in auscultation, whereby sounds are intensified through a column of water.

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hydrophone British  

/ ˈhaɪdrəˌfəʊn /

noun

1. an electroacoustic transducer that converts sound or ultrasonic waves travelling through water into electrical oscillations

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hydrophone Scientific  

/ hī′drə-fōn′ /

1. A device used to detect or monitor sound under water. Hydrophones are often installed or towed in arrays that can be used to pinpoint a sound source or provide sea-floor imaging as part of a sonar system.

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Etymology

Origin of hydrophone

First recorded in 1855–60; hydro- ¹ + -phone

Example Sentences

Each tag recorded extensive information, including motion data, video footage from a lighted camera, hydrophone audio of echolocation clicks, and GPS coordinates.

From Science Daily • Nov. 17, 2025

A hydrophone placed in the water detected movements of the reptiles, which had sonic transmitters attached to their shells.

From National Geographic • Sep. 22, 2023

Alan McKenna, from volunteer research group Loch Ness Exploration, was on a boat using a hydrophone system to capture the underwater sounds of the Highlands loch.

From BBC • Aug. 27, 2023

A hydrophone was also used to detect acoustic signals under the water.

From Reuters • Aug. 27, 2023

At the bottom of the pipe was the hydrophone, a piece of equipment that could pick up the shark’s ping from the tag.

From "The Line Tender" by Kate Allen