(1) A term for certain petroleum products and liquid products of natural gas that have a flash point of -570F, ignition temperature of 5500F, and an explosive range of 1 to 6 percent. See: Petroleum Ether. (2) A Dark Red or Deep Amber Liquid, a mixture of xylene and other chemicals in the same series, with a flash point of 1000F. See: High Flash Naphtha