[ mahy-luh-nahyt, mil-uh- ]
/ ˈmaɪ ləˌnaɪt, ˈmɪl ə- /


Geology. a rock that has been crushed and sheared to such an extent that its original texture has been destroyed.

Origin of mylonite

1885–90; mylon- (representing Greek mýlos mill) + -ite1 Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

British Dictionary definitions for mylonite


/ (ˈmaɪləˌnaɪt, ˈmɪlə-) /


a fine-grained metamorphic rock, often showing banding and micaceous fracture, formed by the crushing, grinding, or rolling of the original structure

Word Origin for mylonite

C19: from Greek mulōn mill
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

Science definitions for mylonite


[ mīlə-nīt′ ]

A fine-grained laminated metamorphic rock in which preexisting minerals have been partially pulverized and drawn out into bands. Mylonite forms along geologic faults where shearing and grinding of rocks takes place.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.