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

Today, most hydrogen is produced through industrial methods that rely on fossil fuels such as petroleum, natural gas, and coal.

From Science Daily • May 20, 2026

So far, the impact has been softened by stored oil inventories, tankers already at sea, releases from strategic petroleum reserves and large inventories in China.

From MarketWatch • May 18, 2026

The strike comes days after the authorities raised petroleum prices to record levels, with costs increasing by more than 20%.

From BBC • May 18, 2026

Still, gains extended beyond petroleum goods, with sales up in nine of the 21 manufacturing segments tracked by Statistics Canada.

From The Wall Street Journal • May 15, 2026

Milton stepped on the gas, ignoring the scarcity not only of petroleum but of many other things as well.

From "Middlesex: A Novel" by Jeffrey Eugenides

Related Words

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