third rail

noun

Updated on: 7 Apr 2018

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

See third rail defined for English-language learners

Examples of third rail in a Sentence

Social Security is the third rail of American politics.

Recent Examples of third rail from the Web

Anyone who thinks Social Security is the third rail of American politics has clearly never talked about firearms with an NRA member.

— james hohmann, Washington Post, "The Daily 202: Democratic committees divided over playing in primaries, with Texas as ground zero," 5 Mar. 2018
Boston fire spokesman Marc Sanders said firefighters received a call around 10:04 p.m. reporting a small fire on the third rail at the T station.

— danny mcdonald, BostonGlobe.com, "Orange Line delayed as firefighters investigate reports of smoke at State Street," 8 Mar. 2018
For many Republicans, the provision to arm teachers is a selling point of a bill filled with gun control measures that have been a third rail of GOP politics for decades.

— gray rohrer, OrlandoSentinel.com, "Senate panel kills assault-weapons ban but approves other gun measures," 27 Feb. 2018
Yet contemporary gun politics has at least partly succeeded in turning the debate over gun laws into a kind of third rail.

— robert j. spitzer, Anchorage Daily News, "Laws we once had on the books could have prevented the Florida school shooting," 16 Feb. 2018
Pulverized stone showered onto the third rail below, before the worker plugged the fresh hole with a length of rubber hose.

— sarah maslin nir, New York Times, "Water, Water Everywhere in New York Subway. And With it, Problems," 12 Feb. 2018
In the third rail car, a seat had fallen onto Dorsey’s legs, her son said.

— meg kinnard, The Seattle Times, "Screams and crying among passengers after Amtrak train crash," 4 Feb. 2018
Just as the president lays his hand on the third rail of race, the athletes are responding.

— michael powell, New York Times, "As Trump Takes On Athletes, Watch Them Rise," 23 Sep. 2017
Stoked by the dissemination powers of the internet, this year was a maelstrom of debate about who wields power, how gender is represented and how artists contend with that third rail of American society: race.

— carolina a. miranda, latimes.com, "In 2017, an angry public demanded the removal of controversial art works. Could the debate limit artistic freedom?," 15 Dec. 2017

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.

First Known Use of third rail

1867

THIRD RAIL Defined for English Language Learners

third rail

noun

Definition of third rail for English Language Learners

: 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

Learn More about third rail

See words that rhyme with third rail Britannica.com: Encyclopedia article about third rail

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third rail

Definition of third rail

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THIRD RAIL Defined for English Language Learners

third rail

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