noun, often attributive
ra·​dar | \ ˈrā-ˌdär \

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

This winter, head to Careyes, an unspoiled, under-the-radar luxury getaway just two hours’ drive from Manzanillo (or three from Puerto Vallarta) along Jalisco’s rugged Pacific coast. Eric Rosen, WSJ, "Escape Winter with a Trip to This Under-the-Radar Destination," 6 Dec. 2018 For almost a decade, the Minutemen mostly flew under the radar, rarely making newspaper headlines, Grover said. Eric Ginsburg, Teen Vogue, "American Nazis and Nazi Sympathizers Have Been Around Since the 1930’s," 26 Nov. 2018 The Mississippi Senate race had mostly flown under the radar, even as election forecasters have classified it as competitive, until last week. Dylan Scott, Vox, "The Mississippi Senate runoff, Dems’ last chance for one more 2018 upset, explained," 20 Nov. 2018 Ellison PoePoe TravelShe’ll arrange for the best tables at under-the-radar restaurants in Vienna and private tours of legendary Habsburg palaces. Paul Brady, Condé Nast Traveler, "2018 Top Travel Specialists We Trust," 19 Oct. 2018 Elverum—who shares Williams under-the-radar vibe—is no stranger to tragedy. Ruby Buddemeyer, Marie Claire, "In 'Vanity Fair,' Michelle Williams Reveals She Secretly Married Musician Phil Elverum," 26 July 2018 And, in a way, Lewerke's under-the-radar July fits snugly into the us-against-the-world ethos Dantonio infuses into his program. Shawn Windsor, Detroit Free Press, "Forget the rankings. MSU's Brian Lewerke could be Big Ten's best QB," 11 July 2018 The Crossover's experts are here to grade all of the under-the-radar deals from this summer. Rob Mahoney, SI.com, "NBA Free Agency 2018: Under-the-Radar Grades," 4 July 2018 Shasta Lake Yurts: Still under the radar, yurts are available at Lakeshore East on the Sacramento Arm of Shasta Lake. Tom Stienstra, SFChronicle.com, "Tom Stienstra: California’s 25 best cabins on golden ponds," 20 June 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

20 Jan 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 \

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

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