petroleum

American  

[puh-troh-lee-uhm] / pəˈtroʊ li əm /

noun

petroleums plural

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

Derived Forms

• petroleous
  adjective

Inflected Forms

Nouns

• petroleums
  plural

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

While crude exports were still up in May, the partial reopening of the strait after the United States and Iran signed a memorandum of understanding helped push petroleum exports towards pre-war levels, Zwemmer said.

From Barron's • Jul. 7, 2026

The energy operations supply various fuels used for heating, cooking and transportation, including liquefied petroleum gas, biopropane and renewable dimethyl ether, as well as diesel oil and gasoline.

From The Wall Street Journal • Jul. 2, 2026

It’s unclear how countries will approach rebuilding their strategic petroleum reserves, and whether industrial demand picks up as producing countries potentially increase supplies, he said.

From MarketWatch • Jul. 2, 2026

In France consumer price rises slowed to 1.8 percent, down from 2.4 percent, statistics authority Insee said, as costs of petroleum products eased.

From Barron's • Jun. 30, 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