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

Since launching Stateside in 2023, TikTok Shop has helped propel a number of emerging brands not just to the top of its own sales charts, but onto the radars of other retailers as well. — Noor Lobad, Footwear News, 8 Sep. 2026

So are your baby monitor, garage door opener, your GPS, the weather-monitoring satellites and the radars keeping planes safely apart. — Aylin Yener, The Conversation, 8 Sep. 2026

According to tracking site FlightRadar24, the plane, which bears the tail number N212ML, appears to have circled off the Bahamian coast before disappearing from radar. — Hanna Park, CNN Money, 8 Sep. 2026

Conspiring online to commit real-world crimes High on the list of groups authorities’ radar is 764, which was founded by an American high school dropout, Bradley Cadenhead. — Lorne Cook, Fortune, 8 Sep. 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