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crude oil

petroleum as it comes from the ground, before refining.
Also called crude, crude petroleum.
1860-65 Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2015.
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Examples from the web for crude oil
  • The process can yield crude oil without the contaminating sulfur that much petroleum out of the ground contains.
  • Also called crude oil petroleum field: noun: geographic area whose rock strata contain oil or gas.
  • It has also been investing in refining, since the export tax on petrol and diesel is lower than that on crude oil.
  • Ground-water contamination by crude oil, and other petroleum-based liquids, is a widespread problem.
  • Petroleum crude oil is by far the largest source of toluene.
  • Higher crude oil prices countered declining oil production and led to higher budgetary and export receipts.
  • We are working to commercialize technology that can make liquid transportation fuels from natural gas instead of crude oil.
  • It could compete with regular crude oil without subsidies.
  • The ocean is home to many groups of bacteria that can break down the chemicals found in crude oil.
  • Each natural gas well produces millions of gallons of wastewater that can be contaminated with salt, chemicals and crude oil.
British Dictionary definitions for crude oil

crude oil

petroleum before it has been refined
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
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crude oil in Science
crude oil
Unrefined petroleum.
The American Heritage® Science Dictionary
Copyright © 2002. Published by Houghton Mifflin. All rights reserved.
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Encyclopedia Article for crude oil

mixture of comparatively volatile liquid hydrocarbons (compounds composed mainly of hydrogen and carbon with some nitrogen, sulfur, and oxygen) that occurs in the Earth's crust and is extracted for use as fuel and various petroleum products. Because crude oil is a mixture of widely varying constituents and proportions, its physical properties also vary widely. For example, the specific gravity, as measured on the American Petroleum Institute (API) gravity scale, may range from 10 to more than 60 and the colour from colourless to black. Crude oil occurs underground, at various pressures from tens to hundreds of kilograms per square centimetre, depending on the depth. Because of the pressure, it contains considerable natural gas in solution. The oil underground is much more fluid than it is on the surface, because the elevated temperatures there (on the average, the temperature rises 1 C for every 33 m [108 feet] of depth) decrease the viscosity.

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Encyclopedia Britannica, 2008. Encyclopedia Britannica Online.
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