vermiculite[vər mik′yə līt′]
vermiculite definition by Webster's New World
Webster's New World College Dictionary Copyright © 2010 by Wiley Publishing, Inc., Cleveland, Ohio. Used by arrangement with John Wiley & Sons, Inc.
any of a number of very soft, monoclinic, hydrous silicate minerals resulting usually from alterations of mica and occurring in tiny, leafy scales that expand greatly when heated: used for insulation, water adsorption, etc.
Origin: ; from Classical Latin vermiculus, diminutive of vermis, worm plush -ite
vermiculite definition by American Heritage Dictionary
Any of a group of micaceous hydrated silicate minerals related to the chlorites and used in heat-expanded form as insulation and as a planting medium.
Origin: Latin vermiculus, diminutive of vermis, worm; see vermicular + -ite1.