sonar(redirected from Passive sonar)
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Related to Passive sonar: active sonar
1. A system using transmitted and reflected underwater sound waves to detect and locate submerged objects or measure the distance to the floor of a body of water.
2. An apparatus, as one in a submarine, using sonar.
[so(und) na(vigation and) r(anging).]
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
(Electronics) a communication and position-finding device used in underwater navigation and target detection using echolocation
[C20: from so(und) na(vigation and) r(anging)]
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014
1. a method for detecting and locating objects submerged in water by echolocation.
2. the apparatus used in sonar.
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.
An electrical impulse is converted into sound waves that are transmitted underwater. The sound waves are reflected off objects in their paths, creating echoes that return to the vessel and are picked up by the sonar equipment.
1. A method of detecting and locating underwater objects, such as submarines or schools of fish, through the use of reflected sound waves. Because the speed of sound in water is constant (about 4,800 feet, or 1,463 meters, per second), the time it takes for a transmitted signal to reach an object and return can be used to calculate the object's distance.
2. The equipment used in doing this.
The American Heritage® Student Science Dictionary, Second Edition. Copyright © 2014 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
A sonic device used primarily for the detection and location of underwater objects. (This term is derived from the words "sound navigation and ranging.")
Dictionary of Military and Associated Terms. US Department of Defense 2005.
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|Noun||1.||sonar - 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"|
measuring device, measuring instrument, measuring system - instrument that shows the extent or amount or quantity or degree of something
navigational instrument - an instrument used for navigating
pinger - a pulse generator used for echo sounding in sonar
pulse generator - a generator of single or multiple voltage pulses; usually adjustable for pulse rate
Based on WordNet 3.0, Farlex clipart collection. © 2003-2012 Princeton University, Farlex Inc.
sonar[ˈsəʊnɑːʳ] N → sonar m
Collins Spanish Dictionary - Complete and Unabridged 8th Edition 2005 © William Collins Sons & Co. Ltd. 1971, 1988 © HarperCollins Publishers 1992, 1993, 1996, 1997, 2000, 2003, 2005
sonar[ˈsəʊnɑːr] n → sonar m
Collins English/French Electronic Resource. © HarperCollins Publishers 2005
Collins German Dictionary – Complete and Unabridged 7th Edition 2005. © William Collins Sons & Co. Ltd. 1980 © HarperCollins Publishers 1991, 1997, 1999, 2004, 2005, 2007
sonar[ˈsəʊnɑːʳ] n → sonar m inv
Collins Italian Dictionary 1st Edition © HarperCollins Publishers 1995