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 most common type of vessel to travel through the strait was the product tanker, which typically transports refined petroleum products. — Tim Lister, CNN Money, 15 Aug. 2026

Seventy million barrels is the strict physical minimum needed at the top of the caverns to keep the extraction pipes safely submerged in oil rather than water, said Siddharth Misra, a petroleum engineering professor at Texas A&M University. — Spencer Kimball, CNBC, 15 Aug. 2026

Novorossiysk also is home to the Grushovaya oil terminal, one of largest international hubs in southern Russia for petroleum products. — ABC News, 12 Aug. 2026

That marks the first time gas prices have been above the $4 mark this late in the year, according to GasBuddy petroleum analyst Patrick De Haan. — Todd C. Frankel, Washington Post, 12 Aug. 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