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

  • n. The property possessed by some crystals of exhibiting different colors, especially three different colors, when viewed along different axes.

from Wiktionary, Creative Commons Attribution/Share-Alike License

  • n. The optical phenomenon in some colored, transparent crystals (such as tourmaline) in which the color is different in different directions.

from the GNU version of the Collaborative International Dictionary of English

  • n. The property possessed by some crystals, of showing different colors when viewed in the direction of different axes.

from The Century Dictionary and Cyclopedia

  • n. In crystallography, the variation in color observed in some crystals when viewed in different directions, due to the fact that the rays having vibrations in different planes suffer absorption in different degrees.

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

  • n. the phenomenon of different colors appearing when certain crystals are viewed from different directions


pleo- + Greek khrōs, color + -ism.
(American Heritage® Dictionary of the English Language, Fourth Edition)



Log in or sign up to get involved in the conversation. It's quick and easy.

  • A rock hound when he is wistful
    dreams gemstones garnered by fistful,
    And rock turned to prism
    By pleochroism -
    The trick of a magical crystal.

    August 20, 2016

  • Purty purty.

    September 30, 2008