Definition of bentonite in English:

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Pronunciation: /ˈben(t)nˌīt/


A kind of absorbent clay formed by the breakdown of volcanic ash, used especially as a filler.
Example sentences
  • Sedimentary rocks such as mudstones often contain a variety of clay minerals, including swelling clays such as bentonite.
  • I work with a low-fire clay body consisting of ball clay, talc and bentonite.
  • Three types of soils, residual soils, kaolinite and bentonite, were used in the study.


Late 19th century: from the name of Fort Benton in Montana, where it is found, + -ite1.

For editors and proofreaders

Syllabification: ben·ton·ite

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