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noun, often attributive ra·dar \ˈrā-ˌdär\

Simple 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)

Source: Merriam-Webster's Learner's Dictionary

Full Definition of radar

  1. 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 (as aircraft) or surface features (as of a planet)

  2. 2 :  range of notice <fell off the radar after losing their first three games>

Examples of radar in a sentence

  1. The approaching planes were detected by radar.

Origin and Etymology of radar

radio detecting and ranging

First Known Use: 1941

Rhymes with radar

Adar, Adzhar, afar, ajar, all-star, armoire, attar, bar car, bazaar, beaux arts, bête noire, beurre noir, Bihar, bizarre, boudoir, boxcar, boyar, Bronze Star, bulbar, Bulgar, bursar, bus bar, canard, cash bar, catarrh, Cathar, chair car, chukar, cigar, clochard, club car, coal tar, cougar, couloir, crossbar, crowbar, Dakar, daystar, debar, decare, devoir, dinar, disbar, Dog Star, drawbar, durbar, earthstar, Elgar, eschar, eyebar, feldspar, fern bar, film noir, five-star, fixed star, flatcar, fluorspar, four-star, fulmar, gaydar, gazar, guitar, Gunnar, Hagar, handcar, horsecar, hussar, Invar, Iyar, jaguar, Kádár, leaf scar, Lehár, lidar, Lifar, Loire, lounge car, lumbar, jack-tar, jowar, Khowar, lahar, lekvar, lodestar, Magyar, malar, memoir, Mylar, NASCAR, Navarre, nightjar, North Star, pace car, paillard, peignoir, pinch bar, Pindar, pine tar, pissoir, planar, plantar, polestar, pourboire, prowl car, pulsar, Qatar, qintar, quasar, railcar, raw bar, rebar, red star, roll bar, Safar, Samar, sandbar, scalar, scout car, Sennar, shofar, sidebar, sidecar, sirdar, sitar, slop jar, slot car, snack bar, sofar, solar, sonar, sports bar, sports car, stock car, streetcar, Svalbard, sway bar, tank car, T-bar, toolbar, town car, tramcar, trocar, unbar, volar, voussoir, Weimar

RADAR Defined for Kids


noun ra·dar \ˈrā-ˌdär\

Definition of radar for Students

  1. :  a radio device for detecting the position of things in the distance and the direction of moving objects (as distant airplanes or ships)

Learn More about radar

Seen and Heard

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to conspire or plot

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