From Longman Dictionary of Contemporary Englishsonarso‧nar /ˈsəʊnɑː, -nə $ ˈsoʊnɑːr, -nər/ noun [uncountable] TTWTEEequipment on a ship or submarine that uses sound waves to find out the position of objects under the water
Examples from the Corpus
sonar• Distinguishing between active sonar returns from mines and returns from rocks and debris on the sea floor is difficult.• The Lowrance company introduced the first civilian sonar in 1957.• And, the Navy is having trouble filling shipboard billets with enough sonar and fire control technicians, who require extensive schooling.• They carry simple Kelvan Hughes sonar and Racal-Decca radar.• Something in the loch has produced some very peculiar sonar traces on some very sophisticated equipment, and that something demands explanation.• A dolphin is able to produce sonar clicks by forcing air through special passages and sinuses in its head.• The sonar watch on the ticking device in the crashed bomber was now continuous.• Navy salvage experts used sonar to help locate the area of submerged wreckage.Origin sonar (1900-2000) sound navigation ranging 