radar

noun

ra·​dar ˈrā-ˌdär How to pronounce radar (audio)
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
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Smith would not comment on Rodriguez’s motive amid ongoing investigation but said that Rodriguez was not on police’s radar before the attack. Miranda Jeyaretnam, Time, 22 May 2025 The likes of Real Madrid and Manchester City also have him on their radars, but not as the top option. David Ornstein, New York Times, 22 May 2025 Some hot-ticket items that should be on your radar include Samsonite’s spacious softside luggage that’s on sale for less than $150. Rylee Johnston, Travel + Leisure, 21 May 2025 Key Facts More than 40 reports of radar and radio failures at dozens of airports nationwide were filed to NASA’s Aviation Safety Reporting System since 2022, CNN reported. Suzanne Rowan Kelleher, Forbes.com, 21 May 2025 See All Example Sentences for radar

Word History

Etymology

radio detecting and ranging

First Known Use

1941, in the meaning defined at sense 1

Time Traveler
The first known use of radar was in 1941

Browse Nearby Words

Cite this Entry

“Radar.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/radar. Accessed 28 May. 2025.

Kids Definition

radar

noun
ra·​dar ˈrā-ˌdär How to pronounce radar (audio)
: 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

More from Merriam-Webster on radar

Last Updated: - Updated example sentences
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