Nitroglycerin Ni`tro*glyc"er*in, n. [Nitro- + glycerinn.] (Chem.) A liquid appearing like a heavy oil, colorless or yellowish, and consisting of a mixture of several glycerin salts of nitric acid, and hence more properly called glycerin nitrate. It is made by the action of nitric acid on glycerin in the presence of sulphuric acid. It is extremely unstable and terribly explosive. A very dilute solution is used in medicine as a neurotic under the name of glonion. [Written also nitroglycerine.] Note: A great number of explosive compounds have been produced by mixing nitroglycerin with different substances; as, dynamite, or giant powder, nitroglycerin mixed with siliceous earth; lithofracteur, nitroglycerin with gunpowder, or with sawdust and nitrate of sodium or barium; Colonia powder, gunpowder with nitroglycerin; dualin, nitroglycerin with sawdust, or with sawdust and nitrate of potassium and some other substances; lignose, wood fiber and nitroglycerin.