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

Fires take many different forms: a motor malfunctions, the third rail smokes. Sean Smyth,, "Looking back on recent MBTA fires," 23 Aug. 2019 But talk of entitlement reform is called the third rail of US politics for a reason: No one will tolerate any talk of a cut to their old age benefits or a payroll tax increase (and both are necessary to pay for these programs). Allison Schrager, Quartz, "Critics of the congressional budget deal are ignoring the really big deal," 24 July 2019 Projects that try to show teens’ lives honestly have often become Hollywood’s third rail. Washington Post, "Creator of HBO’s ‘Euphoria’ says it tries to be ‘empathic’," 1 July 2019 Despite a change in the fuel mix and concerns about ethanol’s environmental cost, challenging U.S. farmers’ share of what is sold at the pump is a political third rail. Lauren Silva Laughlin, WSJ, "On Ethanol, Big Corn Beats Big Oil," 20 June 2019 That's President Trump announcing that Britain's National Health Service would be a part of future trade negotiations between the countries, an idea that had previously been considered a political third rail by both Brits and Americans. Graeme Mcmillan, WIRED, "While You Were Offline: Trump Had a Very Long Week in the UK," 9 June 2019 Even though there is a literal Nazi movement rising in this country, Hitler is the third rail of every conversation, no matter how apt the comparison. Michael Harriot, The Root, "White People Are Cowards," 19 June 2018 One of the nation's most combustible issues, race is a third rail for major corporations, which must appeal to a diverse array of customers. Jessica Guynn, USA TODAY, "ABC's move to ax 'Roseanne' reflects businesses are often at front lines of culture wars," 30 May 2018 Maybe outright comparing black people to apes without even disguising it is a third rail even for Trump people? Jonathan Chait, Daily Intelligencer, "DI Politics Chat: A Low Barr," 29 May 2018

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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Statistics for third rail

Last Updated

7 Sep 2019

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Time Traveler for third rail

The first known use of third rail was in 1867

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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

Comments on third rail

What made you want to look up third rail? Please tell us where you read or heard it (including the quote, if possible).


authorized for issue (as a bond)

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