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third rail

noun

Simple 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

Full Definition of third rail

  1. 1 :  a metal rail through which electric current is led to the motors of an electric vehicle (as a subway car)

  2. 2 :  a controversial issue usually avoided by politicians


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