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.
The high-profile yet under-the-radar pair smartly chose the unusual venue, which has long been the site of rock concerts, athletic events, even the circus, for privacy reasons. Madeleine Marr, Miami Herald, 6 July 2026 Though his first attempt to reach her was unsuccessful, the mention got on Swift's radar, and the duo connected anyway, thanks in part to Taylor's mom. Luke Chinman, PEOPLE, 5 July 2026 Li also said autonomous systems are designed with other sensors such as cameras and radar systems that can compensate for lidar failures. Melissa Lee,paige Tortorelli,scott Zamost, CNBC, 7 July 2026 Quince’s under-the-radar sale section is still going strong, and there’s a surprisingly large selection of deals to shop following the Fourth of July. Katie Decker-Jacoby, StyleCaster, 6 July 2026 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 8 Jul. 2026.

Kids Definition

: 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

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