third rail


Definition of third rail

1 : a metal rail through which electric current is led to the motors of an electric vehicle (such as a subway car)
2 : a controversial issue usually avoided by politicians

Examples of third rail in a Sentence

Social Security is the third rail of American politics.
Recent Examples on the Web Hit first by drought and then by monsoon rains, India suffered an onion shortage that nearly tripled the price in recent months, edging close to a third rail of politics in many countries: the national diet. New York Times, "India Isn’t Letting a Single Onion Leave the Country," 1 Oct. 2019 Healthcare has long been considered the third rail of automotive contract talks. Los Angeles Times, "GM caves on worker healthcare, signaling costs here to stay," 18 Sep. 2019 Over the past decade, the rape joke has become the third rail of comedy. Sophie Gilbert, The Atlantic, "Daniel Sloss Shows How Comedians Should Talk About Rape," 6 Nov. 2019 Democratic lawmakers in recent weeks have begun to advance an argument long seen as something of a third rail in U.S. politics: that slightly less biomedical innovation might be worth a dramatic reduction in drug prices, STAT explains. Ed Silverman, STAT, "Pharmalittle: Congress struggles with drug pricing bill; in Utah, pleas on social media for insulin," 28 Oct. 2019 Despite this curious omission, Murray is unafraid to touch numerous third rails of contemporary discourse. Jeremy Carl, National Review, "Douglas Murray Challenges Us to Oppose Identity Politics and ‘Live in Truth’," 17 Oct. 2019 Photo: stf/Agence France-Presse/Getty Images For decades, France’s conduct in the Algerian War remained a third rail of French politics. Stacy Meichtry, WSJ, "France Acknowledges Torture During Algerian War," 13 Sep. 2018 Cora trailed off, recognizing the potential third rail of admitting that viewers might find some nights unwatchable. Alex Speier,, "Expanded bullpen could make for endless games down the stretch," 4 Sep. 2019 There was also a third rail for power overhead inside the cage. Kevin Leonard,, "The dream of electric trains has origins in Laurel," 6 Sep. 2019

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

1867, in the meaning defined at sense 1

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Time Traveler for third rail

Time Traveler

The first known use of third rail was in 1867

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Cite this Entry

“Third rail.” Dictionary, Merriam-Webster, Accessed 24 Feb. 2020.

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More Definitions for third rail

third rail


English Language Learners Definition of third rail

: a metal rail on a train track that carries electric current to the train's motor
: a difficult issue that politicians try to avoid talking about

More from Merriam-Webster on third rail

Rhyming Dictionary: Words that rhyme with third rail Encyclopedia article about third rail

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