sonar

/ˈsəʊnɑː(r)/ (bre, ipa) · /ˈsəʊnɑːr/ (ame, ipa) · /ˈsō-ˌnär/ (ame, mw)

sonar — noun

1. a device or system that sends sound pulses through water and listens for the ret

1.名詞B2
釋義

a device or system that sends sound pulses through water and listens for the returning echoes, used to detect objects underwater, measure depth, or map the seafloor

例句

The fishing boat's sonar showed a large school of tuna about fifty metres below the surface.

attributive noun: sonar + shows/detects [object]

Submarines rely on sonar to navigate safely through narrow underwater passages and avoid obstacles.

rely on + sonar + to-infinitive purpose clause

同義詞
  • echo sounder

    a simpler type of sonar that specifically measures water depth by sending a single pulse downward

  • asdic

    historical British term for early military sonar systems, rarely used today outside of historical contexts

  • fishfinder

    a small commercial sonar device used by fishing boats to locate fish, less precise than military or research sonar

文法句型

sonar + [noun] (attributive)

detect/locate + by + sonar

用法筆記

Sonar is an uncountable noun that can also function attributively before other nouns (e.g. sonar screen, sonar equipment). Do not treat it as a countable device — you would say 'a sonar system' or 'sonar equipment', not 'a sonar' in formal writing.

常見錯誤

❌The submarine used radar to find the shipwreck.
✅The submarine used sonar to find the shipwreck.
💡Radar uses radio waves for air/atmosphere detection; sonar uses sound waves for underwater detection.
❌We saw a sonar on the bridge.
✅We saw a sonar screen / display on the bridge.
💡Sonar is a system, not a single visible object. Use 'sonar screen', 'sonar display', or 'sonar equipment' for the physical hardware.