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

  • n. A gray, fine-grained volcanic rock, chiefly plagioclase and feldspar.

from Wiktionary, Creative Commons Attribution/Share-Alike License

  • n. A class of fine-grained intermediate igneous rock, of volcanic origin, containing mostly plagioclase feldspar.

from the GNU version of the Collaborative International Dictionary of English

  • n. An eruptive rock allied to trachyte, consisting essentially of a triclinic feldspar, with pyroxene, hornblende, or hypersthene.

from The Century Dictionary and Cyclopedia

  • n. A volcanic rock of wide-spread occurrence, especially in the Cordilleran region of North America.

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

  • n. a dark grey volcanic rock


After the Andes .
(American Heritage® Dictionary of the English Language, Fourth Edition)



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