metamorphism

[ met-uh-mawr-fiz-uh m ]
/ 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.

QUIZZES

HEED THE VOX POPULI, AND TAKE THIS WORD OF THE DAY QUIZ!

Test your memory on these verbal firecrackers from the week of June 29 to July 5!
Question 1 of 7
anchorite

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.