: a method or device for detecting and locating objects especially underwater by means of sound waves sent out to be reflected by the objects
also : a device for detecting the presence of a vessel (such as a submarine) by the sound it emits in water

Examples of sonar in a Sentence

They detected the submarine by using sonar.
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
The 9-and-a-half-foot male shark was tagged by researchers in 2024 and has been detected up and down the outer Cape thousands of times by acoustic sonar. — Neal Riley, CBS News, 21 Oct. 2026 Future versions would also feature a broader array of sensors such as underwater sensors and sonar, as well as larger energy-storage systems. — New Atlas, 17 Oct. 2026 The sonar pinged about once a second, scanning the water 500 feet in every direction for signs of life, while another machine scanned the water immediately below the boat. — Fedor Zarkhin, Los Angeles Times, 13 Oct. 2026 The crews are using craft equipped with sonar to assist in the search. — Eduardo Cuevas, CNN Money, 3 Oct. 2026 See All Example Sentences for sonar

Word History

Etymology

sound navigation ranging

First Known Use

1943, in the meaning defined above

Time Traveler
The first known use of sonar was in 1943

Browse Nearby Words

Cite this Entry

“Sonar.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/sonar. Accessed 2 Nov. 2026.

Kids Definition

: a device for detecting the presence and location of submerged objects (as submarines) by sound waves

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