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.
The conflict in Gaza is an obvious third rail in Hollywood right now. Zak Cheney-Rice, Vulture, 28 Aug. 2025 Avon is rebooting its third rail—expanding into e-commerce, retail, digital and other platforms, to form a new crucial pillar of its global omnichannel strategy. Dean Debiase, Forbes.com, 17 Aug. 2025 The third rail line project was completed on July 15, with the new track able to be used by Union Pacific and Metra trains, a Union Pacific spokesperson told The Beacon-News on Friday. Molly Morrow, Chicago Tribune, 15 Aug. 2025 The Music City Loop won't pose electrical risks like a subway's third rail, the company said. Stuart Dyos, The Tennessean, 12 Aug. 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 9 Sep. 2025.

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