a transparent variety of cordierite, found in Sri Lanka, Madagascar, and elsewhere, sometimes used as a gem.
Origin of water sapphire
First recorded in 1690–1700
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
British Dictionary definitions for water sapphire
a deep blue variety of the mineral cordierite that occurs in Sri Lanka: used as a gemstone
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