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

These materials are key to technologies such as ultrasound, sonar, and high-efficiency sensors, but their complex, disordered structure has remained a mystery for decades. —Mrigakshi Dixit, Interesting Engineering, 30 Apr. 2026

The vessels deploy helicopters and sea drones that use lasers and sonar to find mines. —Aidan Stretch, CBS News, 29 Apr. 2026

Defense Department scientist’s death raises questions MAJOR HEADLINES EYES IN THE SKY — Football field-sized object tracked on sonar at 200 mph, Rep Burchett says. —FOXNews.com, 24 Apr. 2026

Banning forward-facing sonar at certain times of the year? —Mike McFeely, Twin Cities, 24 Apr. 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