from The American Heritage® Dictionary of the English Language, 5th Edition.

  • adjective Derived from magma poured out or ejected at the earth's surface. Used of igneous rocks.

from The Century Dictionary.

  • Capable of being extruded or thrust out; that tends or serves to extrude or thrust out or forth; specifically, in petrography, erupted or extruded: applied to igneous rocks. Same as effusive.
  • noun That which is extruded; specifically, in petrography, same as effusive (which see): contrasted with intrusive.

from the GNU version of the Collaborative International Dictionary of English.

  • adjective (Geol.) Forced out at the surface; ; -- contrasted with intrusive.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

  • adjective Jutting out; extruding.
  • noun geology Rock which has been formed through volcanic extrusion.

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

  • adjective of rock material; forced out while molten through cracks in the earth's surface


Sorry, no etymologies found.



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