sonar
noun /ˈsəʊnɑː(r)/
/ˈsəʊnɑːr/
[uncountable]- equipment or a system for finding objects underwater using sound waves compare radarOxford Collocations DictionarySonar is used before these nouns:
- signal
Word Origin1940s: from so(und) na(vigation and) r(anging), on the pattern of radar.