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third rail

noun

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

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Examples of third rail in a Sentence

  1. Social Security is the third rail of American politics.

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

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

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Examples: third rail in a Sentence