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Portland cement

or portland cement

noun
  1. a type of hydraulic cement usually made by burning a mixture of limestone and clay in a kiln.

Origin of Portland cement

First recorded in 1815–25; named after the Isle of Portland, Dorsetshire, England
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for portland cement

Portland cement

noun
  1. a cement that hardens under water and is made by heating a slurry of clay and crushed chalk or limestone to clinker in a kiln

Word Origin for Portland cement

C19: named after the Isle of Portland, because its colour resembles that of the stone quarried there
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