metamorphism

[ met-uh-mawr-fiz-uhm ]

noun

1. 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.
2. Archaic. metamorphosis.

metamorphism

/ ˌmɛtəˈmɔːfɪzəm /

noun

1. the process by which metamorphic rocks are formed
2. See metamorphosis
   a variant of metamorphosis

metamorphism

/ mĕt′ə-môr′fĭz′əm /

1. The process by which rocks are changed in composition, texture, or structure by extreme heat and pressure.
2. ◆ 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.
3. ◆ 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.
4. See more at contact metamorphism

Word History and Origins

Origin of metamorphism¹

First recorded in 1835–45; meta- + -morphism

Example Sentences

The Weverton sandstone has suffered less from metamorphism than any of the sediments.

From Project Gutenberg

The metamorphism of the igneous rocks is regional in nature and has the same increase from west to east as the sediments.

From Project Gutenberg

Some further remarks upon the subject will be found in the sequel under the heading of Metamorphism.

From Project Gutenberg

Often no granite or other intrusive rock is present which may be regarded as the cause of the metamorphism.

From Project Gutenberg

More than one epoch of metamorphism has perhaps occurred, and the entire record now accessible is exceedingly complicated.

From Project Gutenberg