|a dark-coloured thick flammable crude oil occurring in sedimentary rocks around the Persian Gulf, in parts of North and South America, and below the North Sea, consisting mainly of hydrocarbons. Fractional distillation separates the crude oil into petrol, paraffin, diesel oil, lubricating oil, etc. Fuel oil, paraffin wax, asphalt, and carbon black are extracted from the residue|
|[C16: from Medieval Latin, from Latin petra stone + oleum oil]|
|petroleum (pə-trō'lē-əm) Pronunciation Key
A thick, flammable, yellow-to-black mixture of gaseous, liquid, and solid hydrocarbons that occurs naturally beneath the Earth's surface. It can be separated into fractions including natural gas, gasoline, naphtha, kerosene, paraffin wax, asphalt, and fuel and lubricating oils, and is used as raw material for a wide variety of derivative products. It is believed to originate from the accumulated remains of fossil plants and animals, especially in shallow marine environments.