tran·​spon·​der | \ tran(t)-ˈspän-dər How to pronounce transponder (audio) \

Definition of transponder

: a radio or radar set that upon receiving a designated signal emits a radio signal of its own and that is used especially for the detection, identification, and location of objects and in satellites for relaying communications signals

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Did You Know?

This word was coined during World War II by simply joining pieces of the words transmitter and responder. Transponders are basic to modern aviation and communications satellites, and they're finding new uses in fields such as medicine as well. But they're now also part of everyday life. The "E-ZPass" that lets you drive right through turnpike tollbooths is a transponder, and the car you're driving may not even start unless it recognizes the signal from your personal key's transponder. In a big crowded foot race, you may carry a tiny transponder on your shoe that records when you cross both the starting line and the finish line.

Examples of transponder in a Sentence

Recent Examples on the Web

Their device weighed 2 pounds and could monitor someone using pings from transponders for a half mile. Andrew Boryga,, "Accused rapist takes off, showing that ankle monitors aren’t a perfect solution," 3 July 2019 Most of the tankers had turned off their transponders, which disclose a ship’s location to other boats and coastal authorities. Niharika Mandhana, WSJ, "Fake Signals and Illegal Flags: How North Korea Uses Clandestine Shipping to Fund Regime," 28 Nov. 2018 Shuffling Identities North Korea oil tanker Sam Jong 1 manipulates its transponder to confuse authorities. Niharika Mandhana, WSJ, "Fake Signals and Illegal Flags: How North Korea Uses Clandestine Shipping to Fund Regime," 28 Nov. 2018 Muscat also said the Lifeline turned off its transponder to hide the ship’s location. Washington Post, "Rescuers face scrutiny as 234 migrants reach safe haven," 27 June 2018 That theory is that Zaharie, a veteran pilot, depressurized the plane after turning off its transponder. Washington Post,, "Investigators insist MH370 crash was an accident, not a mass murder-suicide by pilot," 22 May 2018 One driver is accused of racking up more than $90,000 in debts since 2012, mostly in snowballing fees, by using an E-ZPass-only lane more than 1,600 times without a valid transponder, according to a criminal complaint. Scott Calvert, WSJ, "Toll Roads So Tough, Naughty Drivers Are Felons," 6 Apr. 2018 There is no indication of its whereabouts until Aug. 17, when its transponder signal reappears at Nahodka, a port about 100 miles from Vladivostok in Russia’s Far East, the data shows. Joby Warrick, Washington Post, "High seas shell game: How a North Korean shipping ruse makes a mockery of sanctions," 3 Mar. 2018 Es’hail-2 has two transponders on board that can connect to amateur radios from South America to Asia. Loren Grush, The Verge, "Watch SpaceX launch and land a used Falcon 9 rocket," 15 Nov. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'transponder.' 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 transponder

circa 1944, in the meaning defined above

History and Etymology for transponder

transmitter + responder

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Statistics for transponder

Last Updated

12 Jul 2019

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Time Traveler for transponder

The first known use of transponder was circa 1944

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English Language Learners Definition of transponder

technical : a device that receives a radio signal and sends out a signal in response and that is used especially to show the location of something (such as an airplane)

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More from Merriam-Webster on transponder

Rhyming Dictionary: Words that rhyme with transponder

Nglish: Translation of transponder for Spanish Speakers Encyclopedia article about transponder

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