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

An aerial view shows the Chevron EL Segundo refinery, one of the largest petroleum processing facilities in California, on April 8, 2026 as seen from above Manhattan Beach, California. —Lee Ying Shan, CNBC, 14 Apr. 2026

Such a blockade would likely result in further price jumps within a day, said Patrick De Haan, head of petroleum analysis for GasBuddy. —Paula Wethington, CBS News, 13 Apr. 2026

According to Dunn, liquid detergents are based on surfactants and they’re made with oil, either vegetable or crude oil/petroleum. —Melissa Locker, Southern Living, 12 Apr. 2026

By 2019, America had become a net petroleum exporter. —Paul Wiseman, Los Angeles Times, 12 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