How to say "radar" in Japanese

• レーダーCommon
  nounThe ordinary word for radar in any sense—weather radar, navigation, or the figurative 'on someone's radar'. This is the word you want in essentially every context.
  その船ふねにはレーダーが装備そうびされていた。↗

  The boat was equipped with radar.
• 電探でんたん
  nounAn abbreviation for radar, marked as less common. Because it is a shortened form, it is mainly met in technical or military writing rather than everyday speech.
• 電波探知機でんぱたんちき
  nounA longer, less common term for radar, literally a device that detects radio waves. It sounds technical, and レーダー is usually the more natural choice.

For 'radar', use 「レーダー」 in virtually all contexts; 電探 and 電波探知機 are less common alternatives, the former a shortened form best left to specialized or historical usage.

Usage comparisons are AI-assisted and cross-checked by multiple models; for study reference only

• レーダーradar
• 電探でんたんradar
• 電波探知機でんぱたんちきradar