phar·mac·o·lite \färˈmakəˌlīt, fȧˈm-; ˈ ̷ ̷_məkəˌ-\noun (-s) Etymology: German pharmakolith, from pharmako- pharmaco- + lith -lite : a monoclinic mineral CaH(AsO4).2H2O that is a hydrous acid calcium arsenate occurring in silky fibers of a white or grayish color (hardness 2-2.5, specific gravity 2.64-2.73)