- Geology. a change in the structure or constitution of a rock due to natural agencies, as pressure and heat, especially when the rock becomes harder and more completely crystalline.
- Archaic. metamorphosis.
Origin of metamorphism
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
Examples from the Web for metamorphism
Nor is the metamorphism of the invaded rock limited to simple intrusion.The Andes of Southern Peru
A common cause of the metamorphism of rocks is the intrusion into them of igneous rocks.Geology
William J. Miller
This state of things is called general, or normal, metamorphism.The World Before the Deluge
The birthplace of a large variety of ores and minerals is in the zone of metamorphism.North America
Israel C. Russell
How is metamorphism on the large scale supposed to have been induced?Geology
- the process by which metamorphic rocks are formed
- a variant of metamorphosis
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Word Origin and History for metamorphism
Online Etymology Dictionary, © 2010 Douglas Harper
- The process by which rocks are changed in composition, texture, or structure by extreme heat and pressure.♦ In prograde metamorphism metamorphic rocks that were formed under low pressure and temperature conditions undergo a second metamorphic event in which they are exposed to higher pressures and temperatures.♦ In retrograde metamorphism metamorphic rocks that were formed under high pressure and temperature conditions undergo a second metamorphic event in which they are exposed to lower pressures and temperatures. See more at contact metamorphism regional metamorphism.
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