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definitions

clay stone

or clay·stone

noun Geology.
  1. argillite.

Origin of clay stone

First recorded in 1770–80
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Examples from the Web for claystone

Historical Examples of claystone

  • Why should the schist pendant of the Tappock chamber be all right, if the claystone pendant of Dunbuie be all wrong?

  • We see them light their claystone pipes, and send forth clouds of blue vapour.

  • But there was more; close by the stone I noticed (although I think you didn't) a mark in the claystone.

British Dictionary definitions for claystone

claystone

noun
  1. a compact very fine-grained rock consisting of consolidated clay particles
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
claystone in Science

claystone

[klā′stōn′]
  1. A fine-grained, dark gray to pink sedimentary rock consisting primarily of compacted and hardened clay. Claystone is similar to shale but without laminations.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.