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regolith

American  
[reg-uh-lith] / ˈrɛg ə lɪθ /

noun

  1. mantle rock.

regolith British  
/ ˈrɛɡəlɪθ /

noun

  1. the layer of loose material covering the bedrock of the earth and moon, etc, comprising soil, sand, rock fragments, volcanic ash, glacial drift, etc

"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
regolith Scientific  
/ rĕg′ə-lĭth′ /

  1. The layer of rock and mineral fragments that rests on bedrock and is produced by the weathering of rocks. Regolith constitutes the surface of most land.

Etymology

Origin of regolith

1895–1900; < Greek rhêgo ( s ) rug, blanket + -lith

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.