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

Indiana Conservation Officers, Lafayette Fire Department, and the Tippecanoe County Sheriff’s Office water rescue team deployed sonar equipment and boats in hopes of locating the man. —Noe Padilla, IndyStar, 7 July 2025

In early March, the French Navy was conducting an exploratory deep-sea operation off southeastern France when sonar detected a large shape on the seafloor. —Sarah Kuta, Smithsonian Magazine, 18 June 2025

Vessels in the region include littoral combat ships, fast, agile, and networked surface vessels designed for operations close to shore and mine countermeasure vessels, to neutralize mines using advanced sonar systems. —Amira El-Fekki‎ john Feng, MSNBC Newsweek, 18 June 2025

This is happening because the ocean is absorbing increasing amounts of carbon dioxide and because human activity has disturbed the marine food chains, not because wind developers are using sonar. —Anna Broughel, Forbes.com, 7 Aug. 2025

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