petroleum

noun

pe·​tro·​leum pə-ˈtrō-lē-əm 

-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

The vast majority are not for biodiesel or ethanol — the fuel mixed with petroleum for use in cars in parts of the United States, Europe, and Southeast Asia. —Nithin Coca, semafor.com, 23 Apr. 2026

Roughly 20 million barrels per day of oil moved through Hormuz in 2024, equivalent to about one-fifth of global petroleum liquids consumption. —Tenzin Seldon, Fortune, 23 Apr. 2026

Insurance companies stopped covering ships in the region almost immediately, bringing maritime traffic to a standstill on a waterway that normally carries as much as 20% of the world's crude oil and refined petroleum products. —Desiree Adib, ABC News, 22 Apr. 2026

The waterway, a critical oil chokepoint that sits just south of Iran, was responsible for transporting around 20 million to 21 million barrels of oil and petroleum products per day. —David Zimmermann, The Washington Examiner, 22 Apr. 2026

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

Phrases Containing petroleum

• liquefied petroleum gas
• petroleum jelly

Rhymes for petroleum

• folium
• lolium
• oleum
• scholium
• linoleum
• trifolium
• tetrazolium

Kids Definition

petroleum

noun

pe·​tro·​leum pə-ˈtrō-lē-əm 

-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

pe·​tro·​leum pə-ˈtrō-lē-əm, -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