from The American HeritageĀ® Dictionary of the English Language, 4th Edition

  • n. The rail that supplies the high voltage to power a train on an electric railway.
  • n. A subject that tends to be avoided because of its offensive or controversial nature: "Social Security, the 'third rail' of American politicsā€ ( Charles Stein).

from Wiktionary, Creative Commons Attribution/Share-Alike License

  • n. The electrified rail that runs besides, or between train tracks to power electric trains.
  • n. anything that is dangerous to come into contact with, or is best avoided

from the GNU version of the Collaborative International Dictionary of English

  • The third rail used in the third-rail system.
  • An electric railway using such a rail.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

  • n. a rail through which electric current is supplied to an electric locomotive


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  • In politics, Social Security benefits. Don't touch 'em!!

    August 9, 2009