metamorphism

[ met-uh-mawr-fiz-uhm ]
/ ˌmɛt əˈmɔr fɪz əm /

noun

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.

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Origin of metamorphism

First recorded in 1835–45; meta- + -morphism
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2020

Example sentences from the Web for metamorphism

British Dictionary definitions for metamorphism

metamorphism
/ (ˌmɛtəˈmɔːfɪzəm) /

noun

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

Scientific definitions for metamorphism

metamorphism
[ mĕt′ə-môrfĭz′əm ]

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.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.