[met-uh-soh-muh-tiz-uh
m] 
| 1. | the series of metamorphic processes whereby chemical changes occur in minerals or rocks as a result of the introduction of material, often in hot aqueous solutions, from external sources. |
| 2. | replacement (def. 4). |
[ri-pleys-muhnt] | 1. | the act of replacing. |
| 2. | a person or thing that replaces another: summer replacements for vacationing staff; a replacement for a broken dish. |
| 3. | Military. a sailor, soldier, or airman assigned to fill a vacancy in a military unit. |
| 4. | Also called metasomatism. Geology. the process of practically simultaneous removal and deposition by which a new mineral grows in the body of an old one. |
| met·a·so·ma·tism (mět'ə-sō'mə-tĭz'əm) n. The process by which the chemical composition of a rock is changed by interaction with fluids; replacement of one mineral by another without melting. met'a·so·mat'ic (-māt'ĭk) adj., met'a·so·mat'i·cal·ly adv. |
| metasomatism (mět'ə-sō'mə-tĭz'əm) also metasomatosis (mět'ə-sō'mə-tĭz'əm) Pronunciation Key
The process by which the chemical composition of a rock is changed through the introduction or extraction of chemicals dissolved in fluids that migrate through the rock's pores. Metasomatism often results in the formation of new minerals, especially metal ore deposits. |