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

In the first 20 days of May, exports rose nearly 65% year-on-year, led by computing equipment (up 305%), semiconductors (up 202%), and petroleum products (up 46%), easily offsetting a 10% drop in auto exports. —William Pesek, Forbes.com, 28 May 2026

The rainbow sheen of petroleum was plainly visible in nearby surface water. —Jacob Whitehead, New York Times, 27 May 2026

Four years ago Tuesday, 17 Norfolk Southern trains derailed in Harmar Township, Allegheny County, spilling 3,000 gallons of non-flammable petroleum distillate into the Allegheny River. —Megan Shinn, CBS News, 26 May 2026

First, maintaining kiln temperatures hot enough to partially melt rock requires enormous amounts of energy, traditionally supplied by burning coal, petroleum coke, or natural gas. —New Atlas, 26 May 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