A widespread colorless, white, or yellowish mineral, CaSO4·2H2O, used in the manufacture of plaster of Paris, various plaster products, and fertilizers.(noun)
American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Use "gypsum" in a sentence
"In the same manner as sulphur and coal belong to periods of formation very remote from each other, the sal-gem is also found sometimes in transition gypsum, * sometimes in the Alpine limestone, * sometimes in a muriatiferous clay lying on a very recent sandstone, * and lastly, sometimes in a gypsum* posterior to the chalk."
"For its pale translucence, this form of gypsum is known as selenite, named after Selene, the Greek goddess of the moon."
"Apparently the technique was to encase the body in gypsum so that when it decayed it left a perfect cast of the corpse behind."