ETYM Greek kalos beautiful + melas black. So called from its being white, though made from a black mixture of mercury and corrosive sublimate. Related to French calomélas.
A tasteless colorless powder used medicinally as a cathartic; SYN. mercurous chloride.
Strong purgative, compound of mercury, acting on liver.
Hg2Cl2 (technical name mercury(I) chloride) white, heavy powder formerly used as a laxative, now used as a pesticide and fungicide.