noun, often attributive
ra·​dar | \ ˈrā-ˌdär How to pronounce radar (audio) \

Definition of radar

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

And the list of authentically French brands that should be on your radar goes on. Glamour, "The Best French Brands You Haven’t Heard Of Yet," 29 Mar. 2019 Treehouse getaways have been popping up all over our radar—from the ultimate kid's dream playhouse, to the $38 a night Instagram vacay, and even a glass home up in the air, there are ton of options available to live out your childhood fantasy. Elizabeth Gulino, House Beautiful, "This Incredible Treehouse and Zip-Lining Resort Takes Glamping to The Next Level," 29 Mar. 2019 In other words, Farrell’s effortless look puts him back on our radar as our favorite ’00s teen dream, only far better dressed. Liana Satenstein, Vogue, "Forever Heartthrob Colin Farrell Is Polished in a Suit and Sneakers," 26 Mar. 2019 Its radars are designed to be resistant to enemy jamming and reportedly use rapid frequency-hopping and agile beam-steering. Kyle Mizokami, Popular Mechanics, "Bad Weather Ruined a Shipment of Russia’s Best Missiles Bound for China," 19 Feb. 2019 Fiber optic cables also have gotten on his radar, but not for purposes of telecommunication. Sara Castellanos, WSJ, "Chevron CIO Says Technology Triggers Faster Human Decisions," 29 Jan. 2019 Cinemastream is Vox’s series highlighting the most notable of these premieres, in an ongoing effort to keep interesting and easily accessible new films on your radar. Alissa Wilkinson, Vox, "Before you see Welcome to Marwen, stream the documentary about the true story behind it," 21 Dec. 2018 Was the Gary Hart scandal something that was on your radar prior to making this film? Adam Rathe, Town & Country, "The Front Runner's Sara Paxton on Playing Donna Rice and the Unfathomable Glare of Political Scandal," 6 Nov. 2018 Specifically, there are a handful of states to keep on your radar: Florida, New Jersey, Michigan, Utah, Missouri, Oklahoma, Kentucky, and North Dakota. Danielle Corcione, Teen Vogue, "Marijuana in the 2018 Midterms: A State-by-State Guide," 16 Oct. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'radar.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of radar

1941, in the meaning defined at sense 1

History and Etymology for radar

radio detecting and ranging

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Statistics for radar

Last Updated

14 Apr 2019

Look-up Popularity

Time Traveler for radar

The first known use of radar was in 1941

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More Definitions for radar



English Language Learners Definition of radar

: a device that sends out radio waves for finding out the position and speed of a moving object (such as an airplane)


ra·​dar | \ ˈrā-ˌdär How to pronounce radar (audio) \

Kids Definition of radar

: a radio device for detecting the position of things in the distance and the direction of moving objects (as distant airplanes or ships)

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More from Merriam-Webster on radar

Rhyming Dictionary: Words that rhyme with radar

Spanish Central: Translation of radar

Nglish: Translation of radar for Spanish Speakers

Britannica English: Translation of radar for Arabic Speakers

Britannica.com: Encyclopedia article about radar

Comments on radar

What made you want to look up radar? Please tell us where you read or heard it (including the quote, if possible).


having no equal

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