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

The system can monitor more than 500 drones at once, while its radar reaches as far as 37 miles under certain configurations. — Aamir Khollam, Interesting Engineering, 7 July 2026

The authors suspect this similar behavior might be because fighter jets deploy forward-facing weapon-radar systems and dragonflies have a frontally biased vision system ideal for detecting targets in front of them. — Jennifer Ouellette, ArsTechnica, 7 July 2026

The 10th season of the program finds Casillas reemerging to recover his narcotics empire after disappearing from his family’s radar. — Carlos De Loera, Los Angeles Times, 7 July 2026

Li also said autonomous systems are designed with other sensors such as cameras and radar systems that can compensate for lidar failures. — Melissa Lee,paige Tortorelli,scott Zamost, CNBC, 7 July 2026

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
• alvar
• 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