The spelling of the word "petrolen" is incorrect. The correct spelling is "petroleum". The IPA phonetic transcription for "petroleum" is /pəˈtroʊliəm/. This word derives from the Latin word "petra" meaning rock and "oleum" meaning oil. It refers to a naturally occurring liquid consisting of a complex mixture of hydrocarbons, found beneath the Earth's surface. Petroleum is essential for the production of many everyday products such as gasoline, diesel fuel, and plastics, among others.