petroleum

American  

[puh-troh-lee-uhm] / pəˈtroʊ li əm /

noun

1. an oily, thick, flammable, usually dark-colored liquid that is a form of bitumen or a mixture of various hydrocarbons, occurring naturally in various parts of the world and commonly obtained by drilling: used in a natural or refined state as fuel, or separated by distillation into gasoline, naphtha, benzene, kerosene, paraffin, etc.

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petroleum British  

/ pəˈtrəʊlɪəm /

noun

1. 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

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petroleum Scientific  

/ pə-trō′lē-əm /

1. 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.

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Other Word Forms

• petroleous adjective

Etymology

Origin of petroleum

1520–30; < Medieval Latin: literally, rock oil, equivalent to Latin petr ( a ) rock (< Greek pétra ) + oleum oil

Compare meaning

How does petroleum compare to similar and commonly confused words? Explore the most common comparisons:

• petrolatum vs. petroleum

Explanation

Petroleum is oil — a fossil fuel that powers many vehicles and other machinery. Petroleum is a fancy, technical word for something you've probably heard of: oil, an energy source. Petroleum is also known as crude, crude oil, fossil oil, and rock oil. A lot of petroleum is found in the Middle East, and people are always looking for new sources of petroleum. You have to drill for petroleum, because it's deep inside the Earth. There’s a limited amount of petroleum, so many people worry that we're going to use it all up.

Example Sentences

Kenya has sharply raised the cost of petroleum, with diesel prices rising by a record margin despite a fuel tax cut, as the conflict in Iran pushes up global oil prices.

From BBC • Apr. 15, 2026

He said some countries such as South Korea and India that rely heavily on oil and gas coming from the Middle East may need to build new strategic petroleum reserves in the next few years.

From MarketWatch • Apr. 14, 2026

"We have to calculate our monthly expenses, as the money we spend on petroleum has been on the rise," she said.

From Barron's • Apr. 14, 2026

Unable to ship petroleum and liquefied natural gas it had bought from the region, Vitol had to find replacements to send to customers.

From The Wall Street Journal • Apr. 12, 2026

This was fitting because grass, not petroleum, is the foundation of his farm’s success.

From "The Omnivore's Dilemma" by Michael Pollan

Related Words

• crude oil
• fossil fuel
• fuel
• gas
• gasoline
• kerosene
• natural gas
• petrol