Vĭt'ri-ol, n.

n. [Fr. vitriol, Pr. vitriol, vetriol, Sp. & Pg. vitriolo, It. vitriuolo, N. Lat. vitriolum, from Lat. vitrum, glass; from its crystalline form, or its translucency, or perhaps from its color.] (Chem.) (a.) A soluble sulphate of either of the metals. (b.) Sulphuric acid;— popularly so called.

☞ Copperas, or green proto-sulphate of iron, is called green vitriol; a red or flesh-colored sulphate of iron is called red vitriol, or vitriol of Mars; sulphate of copper has a blue color, and is called blue vitriol, or copper vitriol; a white sulphate of zinc is called white vitriol; a sulphate of cobalt is cobalt vitriol, and is called also red vitriol.

Oil of vitriol, sulphuric or vitriolic acid;—popularly so called, because, like oil, when poured from one vessel into another, it makes no noise.