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

As a student at the Colorado School of Mines, Sam Seeton juggled his role as running back for the school’s football team with his pursuit of a petroleum engineering degree, all while managing hunting and fishing access to his family’s ranch outside Buena Vista. —Elise Schmelzer, Denver Post, 13 Oct. 2025

Artificial food colorings were originally manufactured from coal tar, with most synthetic food dyes today made from petroleum, or crude oil, according to the American Chemical Society (ACS) website. —Ashley J. Dimella, FOXNews.com, 12 Oct. 2025

Despite the efforts of site staff and local firefighters, more than 70 million gallons of petroleum products burned or were otherwise released into the environment over the following three days in March 2019. —Philip Steenstra, The Conversation, 9 Oct. 2025

California’s total petroleum product imports have risen to a high of almost 300,000 barrels per day in recent months and threaten to move higher in 2026. —Jordan Blum, Fortune, 9 Oct. 2025

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