What Is The Highly Dangerous Meaning Of “Vitriol”? What is vitriol? Vitriol is an old-fashioned name for one of the most dangerous chemicals you can find: sulfuric acid. This substance is incredibly corrosive, meaning it eats away other substances due to chemical reactions. When sulfuric acid meets water, it produces an exothermic reaction, meaning the chemical reaction that occurs when a chemical mixes with water produces heat. Reactions between the two are responsible for many horrific burns. The acid is so corrosive that, even in diluted form, a drop of it will burn through a piece of paper. Medieval chemists named this substance vitriol after the Latin vitrum, “of glass.” In solid forms, sulfur compounds can have a glass-like appearance (like the image of crystallized copper sulfate). Does vitriol have another meaning? Vitriol has been used poetically to refer to harsh speech since the 1700s. In April, 2010, President Obama referred to some politically-themed talk shows as vitriol. But it wasn’t the only time that the caustic word has been used to describe political discourse. In 2011, Pima County Sheriff Clarence Dupnik cited “vitriolic rhetoric” as a potential source for the shocking attack on Arizona lawmaker Gabrielle Giffords and a crowd of bystanders. The unusual word proliferated through all forms of media.