Cordite is a smokeless explosive that is used as a propellant on Earth during the late-19th century to mid-20th century. It replaced gunpowder (black powder).
The recipe for cordite was present in the databanks on the USS Verdun. In 2163 Commodore Lucian Murat had downloaded the recipe that was then used by the Human forces on Torgu-Va to make this chemical and bullets for the M1 Garand rifle. Doctor Janice Eardman could smell cordite in the air at the Federation Battle Station Torgu-Va. (TNG novel: The Forgotten War)