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

So existing autonomous weapons are comprised of either loitering missiles that smash into radars or quick-firing guns that defend ships and bases. The Economist, "Artificial intelligence is changing every aspect of war," 7 Sep. 2019 And court records show that Wagshol has been on law enforcement’s radar for a decade. courant.com, "Sept. 4, 2019: Dietary advice from a UConn coach," 4 Sep. 2019 Are the Lions trying to keep him off other teams’ radars and sneak him through waivers onto the practice squad? Carlos Monarrez, Detroit Free Press, "Detroit Lions' Josh Johnson makes case for winning backup QB job," 30 Aug. 2019 Offensive line One of the most interesting positions on everyone’s radar at the moment is backup offensive tackle. Bob Mcmanaman, azcentral, "Several Arizona Cardinals will hope to avoid the cut man as NFL rosters trim to 53," 29 Aug. 2019 Toxic algal blooms aren’t high on many people’s radar. Emily Atkin, The New Republic, "The Frightening Spread of Toxic Algae," 28 Aug. 2019 Once the rest of the supplies arrived, chief among their tasks would be to set up the radar instrument, perched at the edge of a bluff overlooking the glacier’s front and encased in a white dome. Denise Chow, NBC News, "My night stranded on the edge of Greenland's fast-melting Helheim Glacier," 17 Sep. 2019 However, cruise missiles and drones fly far closer to the ground, making them harder for radar to detect. Adam Taylor, Washington Post, "Billions spent on U.S. weapons didn’t protect Saudi Arabia’s most critical oil sites from a crippling attack," 17 Sep. 2019 And yet something stirs in Roy when his father lurches back onto the radar. Thomas Page, CNN, "James Gray on 'Ad Astra,' little green men and firing Brad Pitt into space," 16 Sep. 2019

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

13 Oct 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

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