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third rail

noun
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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 In Colorado, which is both an agricultural state and an outdoor recreation magnet, water is not just critical to the economy but an emotional part of the state’s identity and a political third rail. — New York Times, "Wall Street Eyes Billions in the Colorado’s Water," 3 Jan. 2021 Upon being informed of the incident, a rail operations controller shut off power to the third rail around the 7000-series train, as required by protocol. — Washington Post, "Metro has made some progress in correcting safety lapses identified in audit, commission says," 22 Sep. 2020 The commission said Metro also has created a system to ensure that no one is on or near the tracks when power is restored to the electrified third rail after a crash, investigation or other incident. — Washington Post, "Metro has made some progress in correcting safety lapses identified in audit, commission says," 22 Sep. 2020 For most of civilized modernity, baldness remained the third rail of masculinity: Innovations in hairlessness are rare. — Reginald Dwayne Betts Kiese Makeba Laymon Carina Del Valle Schorske Dessa Irina Aleksander Sam Dolnick Mark Binelli Maggie Jones Rob Hoerburger Jamie Lauren Keiles Devin Gordon Jazmine Hughes Jenna Wortham Jade Chang Taffy Brodesser-akner Kaitlyn Greenidge Rowan Ricardo Phillips Michael Paterniti Wesley Morris Ismail Muhammad Anthony Giardina, New York Times, "Remembering some of the artists, innovators and thinkers we lost in the past year.," 23 Dec. 2020 Gun control is often called the third rail of American politics, eliciting strong reactions on both sides of the debate. — Fox News, "Kamala Harris calls to 'honor' Sandy Hook victims with gun reforms," 14 Dec. 2020 Their effort failed, and for generations slavery was largely treated by Congress as a political third rail, to be addressed only at the peril of shattering the Union. — Fergus M. Bordewich, WSJ, "‘A Question of Freedom’ Review: Slavery on Trial," 13 Nov. 2020 But whoever wins next week will have little choice but to stretch out his hand toward the third rail of politics. — Tara Siegel Bernard, New York Times, "Social Security Seemed Like a Future Problem. The Virus Changed That.," 28 Oct. 2020 Meat consumption is the third rail in climate politics. — Jan Dutkiewicz, The New Republic, "Instead of Reengineering Cows, Just Eat Less Meat," 23 Oct. 2020

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

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The first known use of third rail was in 1867

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Statistics for third rail

Last Updated

7 Feb 2021

Cite this Entry

“Third rail.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/third%20rail. Accessed 3 Mar. 2021.

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More Definitions for third rail

third rail

noun

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

See the full definition for third rail in the English Language Learners Dictionary

More from Merriam-Webster on third rail

Thesaurus: All synonyms and antonyms for third rail

Britannica.com: Encyclopedia article about third rail

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