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

  • n. A steel-gray to black mineral, MnO(OH), found in North America and Europe; manganese oxide.

from Wiktionary, Creative Commons Attribution/Share-Alike License

  • n. a dark gray mineral of manganese, MnO(OH), found throughout North America and Europe

from the GNU version of the Collaborative International Dictionary of English

  • n. One of the oxides of manganese; -- called also gray manganese ore. It occurs in brilliant steel-gray or iron-black crystals, also massive.
  • n. A compound of manganese dioxide with a metallic oxide; so called as though derived from the hypothetical manganous acid.

from The Century Dictionary and Cyclopedia

  • n. A hydrated oxid of manganese occurring in orthorhombic crystals of a steel-gray or iron-black color and brilliant luster, also in masses having a columnar structure. It is often altered, by loss of water, to pyrolusite. Also called gray manganese ore.
  • n. A substance which may be viewed as a compound of manganese dioxid with the monoxid of a more basic or electropositive metal.

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

  • n. a black mineral consisting of basic manganese oxide; a source of manganese


Sorry, no etymologies found.



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