radar

noun

ra·​dar ˈrā-ˌdär 

often attributive

1

: a device or system consisting usually of a synchronized radio transmitter and receiver that emits radio waves and processes their reflections for display and is used especially for detecting and locating objects (such as aircraft) or surface features (as of a planet)

2

: range of notice

fell off the radar after losing their first three games

Examples of radar in a Sentence

The approaching planes were detected by radar.

Recent Examples on the Web

Another complication is that the radome needs to be transparent to radar signals. —Christopher McFadden, Interesting Engineering, 13 Dec. 2025

Headlines have been made of artworks repatriated to their countries of origin, but meanwhile the issue of illicit antiquities continues to largely go under the radar. —Lianne Kolirin, CNN Money, 13 Dec. 2025

Still, another cold front is on forecasters' radar after the warmup next week, the National Weather Service said. —Jeanine Santucci, USA Today, 13 Dec. 2025

Live Indianapolis, Indiana weather radar Is there snow on the ground? —Katie Wiseman, IndyStar, 12 Dec. 2025

Word History

Etymology

radio detecting and ranging

First Known Use

1941, in the meaning defined at sense 1

Phrases Containing radar

• anti-radar
• Doppler radar
• fall off the radar
• on someone's radar (screen)
• radar astronomy
• radar beacon
• radar cruise control
• radar detector
• radar gun
• under the radar

Rhymes for radar

• adar
• afar
• ajar
• alar
• ansar
• bazaar
• bizarre
• boxcar
• boyar
• bulbar
• cachar
• cigar

Kids Definition

radar

noun

ra·​dar ˈrā-ˌdär 

: a device that sends out radio waves for detecting and locating an object by the reflection of the radio waves and that may use this reflection to find out the position and speed of the object

Etymology

from radio detecting and ranging