A combustible substance is any material that can be easily ignited and burned. Common examples of combustible substances include FUEL, COAL, pyres, tinder, and PYRE. FUEL is a flammable liquid or gas used to produce energy, such as gasoline or diesel. COAL is a black or dark brown sedimentary rock composed mainly of carbon and hydrocarbons. Pyres are large piles of wood or other combustible materials used for burning a corpse as part of a funeral ritual. Tinder is a highly flammable material used to start a fire. PYRE is an alternative spelling of pyres.