Dictionary.com
definitions
  • synonyms
British Dictionary definitions for permanent hardness

permanent hardness

noun
  1. chem hardness of water that cannot be removed by boiling as it results mainly from the presence of calcium and magnesium chlorides and sulphates
Show More
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