sonar, echo sounder, asdic(noun)
a measuring instrument that sends out an acoustic pulse in water and measures distances in terms of the time for the echo of the pulse to return
"sonar is an acronym for sound navigation ranging"; "asdic is an acronym for antisubmarine detection investigation committee"
A device that uses hydrophones (in the same manner as radar) to locate objects underwater.
Sonar is a technique that uses sound propagation to navigate, communicate with or detect objects on or under the surface of the water, such as other vessels. Two types of technology share the name "sonar": passive sonar is essentially listening for the sound made by vessels; active sonar is emitting pulses of sounds and listening for echoes. Sonar may be used as a means of acoustic location and of measurement of the echo characteristics of "targets" in the water. Acoustic location in air was used before the introduction of radar. Sonar may also be used in air for robot navigation, and SODAR is used for atmospheric investigations. The term sonar is also used for the equipment used to generate and receive the sound. The acoustic frequencies used in sonar systems vary from very low to extremely high. The study of underwater sound is known as underwater acoustics or hydroacoustics.
Dictionary of Military and Associated Terms
A sonic device used primarily for the detection and location of underwater objects. (This term is derived from the words
The numerical value of sonar in Chaldean Numerology is: 9
The numerical value of sonar in Pythagorean Numerology is: 4