sonar

American  

[soh-nahr] / ˈsoʊ nɑr /

noun

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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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

Example Sentences

Rescuers continue their search, aided by divers and sonar systems, Fathur said.

From Barron's

Water temperature layers and changing salinity from melting ice interfere with sonar.

From The Wall Street Journal

A sonobuoy is a combination of the words sonar and buoy and is an acoustic sensor used to detect underwater objects such as submarines.

From BBC

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 Literature

"It's an unspoken rule, but it's what we are adhering to for the first time: there will be no active acoustic program on board the ship, no sonar" while in Russian waters, he explained.

From Barron's