petroleum

noun

pe·​tro·​leum pə-ˈtrō-lē-əm How to pronounce petroleum (audio)
-ˈtrōl-yəm
: an oily flammable bituminous liquid that may vary from almost colorless to black, occurs in many places in the upper strata of the earth, is a complex mixture of hydrocarbons with small amounts of other substances, and is prepared for use as gasoline, naphtha, or other products by various refining processes

Examples of petroleum in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
So too did a record 400-million-barrel release from the International Energy Agency’s strategic petroleum reserves – a supply boost that’s still underway. David Goldman, CNN Money, 25 June 2026 Patrick De Haan, head of petroleum analysis at GasBuddy, predicts the national average for a gallon of regular gasoline could fall below $3 later this year. Erin Mansfield, USA Today, 24 June 2026 Other barges move fertilizer, coal, petroleum, cement, and steel. Alfredo Sosa, Christian Science Monitor, 24 June 2026 But in 2024, a Los Angeles County Superior Court judge invalidated the law, ruling that the state, not the city, has jurisdiction over petroleum production. Los Angeles Times, 23 June 2026 See All Example Sentences for petroleum

Word History

Etymology

Middle English, "mineral oil," borrowed from Medieval Latin, "mineral oil, crude oil," from Latin petra "rock" (borrowed from Greek pétra) + oleum "oil" — more at petro-, oil entry 1

First Known Use

15th century, in the meaning defined above

Time Traveler
The first known use of petroleum was in the 15th century

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Cite this Entry

“Petroleum.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/petroleum. Accessed 30 Jun. 2026.

Kids Definition

petroleum

noun
pe·​tro·​leum pə-ˈtrō-lē-əm How to pronounce petroleum (audio)
-ˈtrōl-yəm
: an oily flammable liquid that may vary from almost colorless to black, is obtained from wells drilled in the ground, and is the source of gasoline, kerosene, fuel oils, and other products

Medical Definition

petroleum

noun
: an oily flammable bituminous liquid that may vary from almost colorless to black, occurs in many places in the upper strata of the earth, is a complex mixture of hydrocarbons with small amounts of other substances, and is prepared for use as gasoline, naphtha, or other products by various refining processes

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