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diatomaceous earth

noun
  1. a fine siliceous earth composed chiefly of the cell walls of diatoms: used in filtration, as an abrasive, etc.

Origin of diatomaceous earth

First recorded in 1880–85
Also called di·at·o·mite [dahy-at-uh-mahyt] /daɪˈæt əˌmaɪt/, kieselguhr.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for diatomaceous earth

diatomaceous earth

noun
  1. an unconsolidated form of diatomiteAlso called: kieselguhr
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
diatomaceous earth in Medicine

diatomaceous earth

[dī′ə-tə-mā′shəs, dī-ăt′ə-]
n.
  1. A powder made of the desiccated shells of diatoms, used as a filtering agent, adsorbent, and abrasive in many chemical operations.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.