third rail

noun

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
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
In political discourse, DEI became the ultimate third rail. Sheilla Mamona, refinery29.com, 18 Feb. 2025 For decades, transfer remained the third rail of Israeli politics - so extreme, so indefensible, that it could not be spoken of in polite company. Thomas G. Moukawsher, Newsweek, 5 Feb. 2025 The Times reported that if Lynskey or his clothes had touched the third rail, which runs outside the track and electrifies the subway, chances are he would've been electrocuted. Becca Longmire, People.com, 4 Feb. 2025 In the health insurance realm, for example, the Affordable Care Act provides subsidized health insurance for many Americans, and changing Medicare is a political third rail. Jay Feinman, The Conversation, 15 Jan. 2025 See All Example Sentences for third rail

Word History

First Known Use

1867, in the meaning defined at sense 1

Time Traveler
The first known use of third rail was in 1867

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Cite this Entry

“Third rail.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/third%20rail. Accessed 3 Mar. 2025.

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