C1noun3K

Radar

UK /["/ˈreɪdɑː(r)/"]/US /["/ˈreɪdɑːr/"]/

Definition

a system that uses radio waves to find the position and movement of objects, for example planes and ships, when they cannot be seen

In simple words: A system that uses waves to find objects and measure their distance.

Examples

  • They located the ship by radar.
  • a radar screen
  • The aircraft suddenly went off the radar.
  • The submarine is impossible to detect on radar.
  • navigation by radar
  • Experts say a lot of corporate crime stays under the radar.
  • The conflict has slipped below the radar of the media.
  • The issue of terrorism is back on the radar screen.
  • Since the scandal broke, all other issues seem to have **disappeared off the radar screen** as far as the media is concerned.

Usage notes

Used in contexts related to navigation, weather, and security. Avoid in casual conversations unless discussing technology. Works in both spoken and written communication.

Grammar pattern

standalone noun

Memory hint

Think of 'radar' as 'RAdio Detection And Ranging'.

Collocations

  • enemy
  • police
  • airborne
  • be equipped with
  • operator
  • station
  • system
  • by radar
  • on radar
  • off the radar
  • on the radar

Synonyms

  • detector
  • sonar
  • locator

Antonyms

  • invisibility
  • undetectability

Common mistakes

  • Confused with 'racer' because of similar spelling.
  • Incorrectly pronounced as 'ray-dar' instead of 'rad-ar'.
  • Used inappropriately in non-technical contexts.