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 But even though Missoma’s roster is star-studded, the brand is still relatively under the radar. Shanna Shipin, Glamour, "Missoma Black Friday Sale 2020: What to Buy From the Celeb-Loved Brand," 19 Nov. 2020 The hope, in the many years when mRNA vaccine research flew under the radar, was that the technology would deliver results quickly in a pandemic. Sarah Zhang, The Atlantic, "The End of the Pandemic Is Now in Sight," 18 Nov. 2020 The unknown While his competitors were being tipped to succeed at a Masters unusually held in November and without spectators because of the coronavirus pandemic, Johnson started the tournament relatively under the radar. Ben Morse, CNN, "Is golf set for a new era of dominance after Dustin Johnson smashes records to win Masters?," 16 Nov. 2020 Fans learned Swift was dating Alwyn in May 2017, though the pair kept things under the radar for months. Jenna Ryu, USA TODAY, "Taylor Swift provides rare glimpse into her relationship with Joe Alwyn," 13 Nov. 2020 In the recruiting process, Pohto was under the radar since his exposure was minimized during the AAU season because of the pandemic. Marcus Fuller, Star Tribune, "Swedish big man Kenny Pohto talks Gophers signing and major growth," 11 Nov. 2020 Some of those issues are under the radar, but others include big-ticket items like infrastructure, prescription-drug pricing and elements of the COVID-19 relief efforts. Tom Benning, Dallas News, "Biden could be 1st new president since Bush 41 to face divided Congress. What does that mean for his agenda?," 8 Nov. 2020 So how has an entire species managed to fly under the radar for so long? Daisy Hernandez, Popular Mechanics, "This Remarkable Chameleon Disappeared 107 Years Ago. It Just Returned.," 5 Nov. 2020 Infectious-disease specialists caution that the virus could be spreading under the radar. Washington Post, "Canadian provinces work to keep schools open amid coronavirus second wave," 2 Nov. 2020

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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Time Traveler for radar

Time Traveler

The first known use of radar was in 1941

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Statistics for radar

Last Updated

22 Nov 2020

Cite this Entry

“Radar.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/radar. Accessed 24 Nov. 2020.

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More Definitions for radar


How to pronounce radar (audio)

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

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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