färˈmakəˌlīt, fȧˈm-; ˈ ̷ ̷_məkəˌ- noun
( -s )
Etymology: German pharmakolith, from pharmako- pharmaco- + lith -lite
: a monoclinic mineral CaH(AsO 4 ).2H 2 O 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)