a white, crystalline, water-insoluble, tasteless powder, CaCO3, occurring in nature in various forms, as calcite, chalk, and limestone: used chiefly in dentifrices and polishes and in the manufacture of lime and cement.
A white or colorless crystalline compound occurring naturally in chalk, limestone, and marble and in the minerals calcite and aragonite. It is used to make toothpaste, white paint, and cleaning powder. Chemical formula: CaCO3.
