Emily Dickinson Lexicon

GYP'SUM, n. [L. from Gr. γυψος; Ch. גופיס and גפס to overspread with plaster; Ar. جِبْسِينٌ gibsinin.]

Plaster stone; sulphate of lime; a mineral not unfrequently found in crystals, often in amorphous masses. There are several subspecies and varieties; as, the foliated, compact, earthy, granular, snowy, and branchy. Cleaveland. Gypsum is of great use in agriculture and the arts. As a manure, it is invaluable.