pyrophyllite 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.
a very soft, greasy, monoclinic mineral, AlSiO(OH), that is similar to talc in structure, used as a lubricant and in making rubber, soap, etc.; hydrous aluminum silicate
Origin: German pyrophyllit: see pyro- and amp; phyll(o)- and amp; -ite
pyrophyllite definition by American Heritage Dictionary
A silvery white or pale green aluminum silicate mineral, Al2Si4O10(OH)2, occurring naturally in soft compact masses.