sonar

[ soh-nahr ]
/ ˈsoʊ nɑr /

noun

a method for detecting and locating objects submerged in water by echolocation.
the apparatus used in sonar.

Origin of sonar

1940–45; so(und) na(vigation) r(anging)
Also called, British, asdic.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for sonar

British Dictionary definitions for sonar

sonar

/ (ˈsəʊnɑː) /

noun

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

Word Origin for sonar

C20: from so (und) na (vigation and) r (anging)
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Science definitions for sonar

sonar

[ sōnär′ ]

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.
The equipment or physiology used in doing this. See also Doppler effect lidar radar.
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