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radar

[ rey-dahr ]
/ ˈreɪ dɑr /
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noun
Electronics. a device for determining the presence and location of an object by measuring the time for the echo of a radio wave to return from it and the direction from which it returns.
a means or sense of awareness or perception: lobbyists working under the media's radar.

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Origin of radar

1940–45, Americanism;ra(dio)d(etecting)a(nd)r(anging)

OTHER WORDS FROM radar

an·ti·ra·dar, noun, adjective
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

How to use radar in a sentence

British Dictionary definitions for radar

radar
/ (ˈreɪdɑː) /

noun
a method for detecting the position and velocity of a distant object, such as an aircraft A narrow beam of extremely high-frequency radio pulses is transmitted and reflected by the object back to the transmitter, the signal being displayed on a radarscope. The direction of the reflected beam and the time between transmission and reception of a pulse determine the position of the objectFormer name: radiolocation
the equipment used in such detection

Word Origin for radar

C20 ra (dio) d (etecting) a (nd) r (anging)
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Scientific definitions for radar

radar
[ rādär ]

A method of detecting distant objects and determining their position, speed, material composition, or other characteristics by causing radio waves to be reflected from them and analyzing the reflected waves. The waves can be converted into images, as for use on weather maps.
The equipment used in such detecting. See also Doppler effect lidar sonar.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

Cultural definitions for radar

radar

A method of finding the position and velocity of an object by bouncing a radio wave off it and analyzing the reflected wave. Radar is an acronym for radio detection and ranging.

notes for radar

Police use radar techniques to determine the speed of automobiles.
The New Dictionary of Cultural Literacy, Third Edition Copyright © 2005 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
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