Cal"o*mel (kăl"&osl;*m&ebreve;l), n. [Gr. kalo`s beautiful + me`las black. So called from its being white, though made from a black mixture of mercury and corrosive sublimate. Cf. F. calomélas.] (Chem.) Mild chloride of mercury, Hg₂Cl₂, a heavy, white or yellowish white substance, insoluble and tasteless, much used in medicine as a mercurial and purgative; mercurous chloride. It occurs native as the mineral horn quicksilver.