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

Sulfur is relatively inexpensive and widely available, including as a byproduct of petroleum refining and natural gas processing. — Rupendra Brahambhatt, Interesting Engineering, 20 Sep. 2026

The narrow strait linking the Red Sea to the Gulf of Aden is one of the world’s busiest maritime shipping routes, accounting for about 7% of the global petroleum trade. — Dominique Soguel, Christian Science Monitor, 19 Sep. 2026

One is refiners with strong distillate margins that benefit from a wider crack spread — the difference between crude oil prices and wholesale petroleum-product prices. — Kevin Williams, CNBC, 17 Sep. 2026

Like many former industrial sites, Hazelwood Green contained soil contaminated with petroleum hydrocarbons, heavy metals and other pollutants, resulting in its classification as a brownfield. — Catherine Armbruster, The Conversation, 17 Sep. 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