sonar

noun

so·​nar ˈsō-ˌnär 

: a method or device for detecting and locating objects especially underwater by means of sound waves sent out to be reflected by the objects

also : a device for detecting the presence of a vessel (such as a submarine) by the sound it emits in water

Examples of sonar in a Sentence

They detected the submarine by using sonar.

Recent Examples on the Web

Crews have searched 2,840 square miles and are preparing to use sonar to examine the seabed, 80 to 90 feet beneath the surface. — John Raby, Los Angeles Times, 4 Oct. 2026

The crews are using craft equipped with sonar to assist in the search. — Eduardo Cuevas, CNN Money, 3 Oct. 2026

Before forward-facing sonar, anglers studied past tournaments and memorized successful fishing patterns at various times of the year. — Bryan Hendricks, Arkansas Online, 27 Sep. 2026

Fothergill, who grew up in Minnesota idolizing Moss, said his partner held his own on the water, using forward-facing sonar to locate fish sitting 70 to 90 feet deep. — Amber Harding Outkick, FOXNews.com, 31 Aug. 2026

Word History

Etymology

sound navigation ranging

First Known Use

1943, in the meaning defined above

Phrases Containing sonar

• side-scan sonar

Kids Definition

sonar

noun

so·​nar ˈsō-ˌnär 

: a device for detecting the presence and location of submerged objects (as submarines) by sound waves