sonar

American  

[soh-nahr] / ˈsoʊ nɑr /

noun

• sonars
  plural

1. a method for detecting and locating objects submerged in water by echolocation.

2. the apparatus used in sonar.

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sonar British  

/ ˈsəʊnɑː /

noun

1. a communication and position-finding device used in underwater navigation and target detection using echolocation

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sonar Scientific  

/ sō′när′ /

1. Short for sound navigation and ranging. A method of detecting, locating, and determining the speed of objects through the use of reflected sound waves. A sound signal is produced, and the time it takes for the signal to reach an object and for its echo to return is used to calculate the object's distance. The Doppler effect can also be used to determine the object's relative velocity. Electronic sonar systems are used for submarine navigation and for detecting schools of fish. Some mammals, especially bats, use biological sonar to navigate and detect prey in dark conditions, commonly called echolocation.

2. The equipment or physiology used in doing this.

3. See also Doppler effect lidar radar

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Other Word Forms

Noun Inflected Forms

• sonars
  plural

Etymology

Origin of sonar

1940–45; so(und) na(vigation) r(anging)

Compare meaning

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

• sonar vs. radar

Explanation

Sonar is a method of finding objects under water using sound waves. If the Titanic had been able to use sonar, it never would have hit that iceberg. There are two kinds of sonar: active sonar, which sends sounds out and listens for their echoes, and passive sonar, which records existing sounds. Both allow boat and submarine pilots, explorers, the military, and scientists to determine how far away underwater objects are and approximately how large they are. Leonardo da Vinci gets the credit for inventing sonar when he inserted a tube in the water and listened for the sound of distant ships in 1490.

Example Sentences

See Examples For:

sonar sonars

The Carbondale, Ill., wonder, who grew up fishing a pond in his backyard, rocketed up the sport with his wizardry for forward-facing sonar.

From The Wall Street Journal ● Aug. 29, 2026

The San Francisco Police Department has been using boat-mounted sonar to search for the vessel since Tuesday and located its remains Friday.

From Los Angeles Times ● Jul. 18, 2026

The aerospace and defense contractor said Monday that Ultra Maritime’s portfolio of anti-submarine warfare will complement and expand its ability to offer sonar solutions for maritime platforms.

From The Wall Street Journal ● Jul. 6, 2026

The monitoring devices which were believed to have been dropped by the Bear-F plane float on the water and use sonar to detect submarines and other vessels.

From BBC ● Jul. 6, 2026

Of all the innovations and technical advancements that have made the discovery and excavation of shipwrecks increasingly possible, none has been more important than the invention and continual development of side-scan sonar.

From "Shipwrecked!" by Martin W. Sandler

Mayer and other scientists argued that emerging technologies, especially multibeam sonars that produce detailed 3D images, offered an unprecedented opportunity to document little known sea floors off the U.S.

From Science Magazine ● Jan. 8, 2024

“You use sonars to verify ranges and they might have been testing the sonar or working out the echo strength of the sonar,” the source told The Times.

From Washington Times ● Nov. 19, 2023

Using a variety of sonars and two remotely operated vehicles — Deep Discoverer and Serios — researchers aboard the ship are mapping and collecting samples from areas along the Aleutian Trench and Gulf of Alaska.

From Seattle Times ● Aug. 14, 2023

National Marine Fisheries Service that concluded the Navy had "killed at least six whales in an accident involving common ship-based sonars."

From Salon ● Jan. 19, 2023

Tom filtered out the difference in the two sounds with the correlation calculator unit of one of his quality analyzer sonars.

From Tom Swift and the Electronic Hydrolung by Charles Brey