• synonyms


  1. any of a group of clay minerals characterized by the ability to expand when they absorb large quantities of water.
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Origin of montmorillonite

1850–55; named after Montmorillon, France, where it was found; see -ite1
Also called smectite.
Related formsmont·mo·ril·lon·it·ic [mont-muh-ril-uh-nit-ik] /ˌmɒnt məˌrɪl əˈnɪt ɪk/, adjective
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

British Dictionary definitions for montmorillonite


  1. a clay mineral consisting of hydrated aluminium silicate: an important component of bentonite
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Word Origin

C19: named after Montmorillon, French town where it was first found, + -ite 1
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