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Synonyms

oil

American  
[oil] / ɔɪl /

noun

  • oils
    plural
  1. any of a large class of substances typically unctuous, viscous, combustible, liquid at ordinary temperatures, and soluble in ether or alcohol but not in water: used for anointing, perfuming, lubricating, illuminating, heating, etc.

  2. a substance of this or similar consistency.

  3. refined or crude petroleum.

  4. Painting.

    1. oil color.

    2. oil painting.

  5. Informal. unctuous hypocrisy; flattery.

  6. an oilskin garment.

  7. Australian and New Zealand Slang. facts or news; information.

    good oil.


verb (used with object)

  • oils,
    present (3rd person singular)
  • oiled,
    past participle,  past
  • oiling
    present participle
  1. to smear, lubricate, or supply with oil.

  2. to bribe.

  3. to make unctuous or smooth.

    to oil his words.

  4. to convert into oil by melting, as butter.

adjective

  1. pertaining to or resembling oil.

  2. using oil, especially as a fuel.

    an oil furnace.

  3. concerned with the production or use of oil.

    an offshore oil rig.

  4. made with oil.

  5. obtained from oil.

idioms

  1. pour oil on troubled waters, to attempt to calm a difficult or tense situation, as an argument.

  2. strike oil,

    1. to discover oil, especially to bring in a well.

    2. to have good luck, especially financially; make an important and valuable discovery.

      They struck oil only after years of market research.

oil British  
/ ɔɪl /

noun

  1. any of a number of viscous liquids with a smooth sticky feel. They are usually flammable, insoluble in water, soluble in organic solvents, and are obtained from plants and animals, from mineral deposits, and by synthesis. They are used as lubricants, fuels, perfumes, foodstuffs, and raw materials for chemicals See also essential oil fixed oil

    1. another name for petroleum

    2. ( as modifier )

      an oil engine

      an oil rig

    1. Also called: lubricating oil. any of a number of substances usually derived from petroleum and used for lubrication

    2. ( in combination )

      an oilcan

      an oilstone

    3. ( as modifier )

      an oil pump

  2. Also called: fuel oil. a petroleum product used as a fuel in domestic heating, industrial furnaces, marine engines, etc

    1. paraffin, esp when used as a domestic fuel

    2. ( as modifier )

      an oil lamp

      an oil stove

  3. any substance of a consistency resembling that of oil

    oil of vitriol

  4. the solvent, usually linseed oil, with which pigments are mixed to make artists' paints

    1. (often plural) oil colour or paint

    2. ( as modifier )

      an oil painting

  5. an oil painting

  6. slang facts or news

    1. to discover petroleum while drilling for it

    2. informal to become very rich or successful

"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

verb

  1. to lubricate, smear, polish, etc, with oil or an oily substance

  2. informal to bribe (esp in the phrase oil someone's palm )

  3. to make things run smoothly

  4. See well-oiled

"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
oil Scientific  
/ oil /
  1. Any of a large class of viscous liquids that are typically very slippery and greasy. Oils are composed mostly of glycerides. They are flammable, do not mix with water, and include animal and vegetable fats as well as substances of mineral or synthetic origin. They are used in food, soap, and candles, and make good lubricants and fuels.

  2. See essential oil mineral oil petroleum


oil More Idioms  
  1. see banana oil; burn the midnight oil; grease (oil) someone's palm; grease (oil) the wheels; pour oil on troubled waters; strike it rich (oil).


Other Word Forms

Derived Forms

Inflected Forms

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Participles

Conjugated Forms

Present

Past

Future

Etymology

Origin of oil

1125–75; Middle English olie, oile < Old French < Latin oleum, olīvum (olive) oil < *oleivum ( cf. Deus) < dialectal Greek *élaiwon ( Attic élaion ), derivative of *elaíwā olive

Explanation

Oil is a liquid fat or fuel. You might dress your salad with olive oil and use motor oil in your car's engine; just don't confuse the two! There's the oil you put in your car or use to oil a rusty lock — then there's the oil you heat to stir fry vegetables or whisk with vinegar to make salad dressing. Chemically, these oils have a lot in common, from their tendency to avoid water to their slipperiness to the ease with which they catch on fire. Still, you'd never want to toss a bowl of spaghetti with motor oil — stick to olive oil instead.

Keep Reading on Vocabulary.com

Vocabulary lists containing oil

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

See Examples For:

During frigid weather, gas plants without adequate supply turn to burning oil, which is expensive and not exactly clean.

From The Wall Street Journal ● Oct. 7, 2026

Alberta is home to Canada's oil and gas sector, with oil reserves estimated to be the fourth-largest in the world.

From BBC ● Oct. 7, 2026

There are seagull puppets, a tandem bicycle, an oil stain in the shape of a rabbit, a meteorite.

From Los Angeles Times ● Oct. 7, 2026

Shell and other oil majors are seeing "an unprecedented widening of the refining spread", said Kathleen Brooks, research director at trading group XTB.

From Barron's ● Oct. 7, 2026

Aunt Kitty was in such a hurry, we left the oil lamp and the poker behind.

From "The Detective's Assistant" by Kate Hannigan

Those roots contain fragrant compounds that can be extracted to make essential oils.

From Science Daily ● Oct. 6, 2026

Scientists have previously investigated oils produced from Hinoki leaves and branches, but oils derived specifically from the roots have received far less attention.

From Science Daily ● Oct. 6, 2026

Costco recently raised the price of its private-label Kirkland motor oils to $58 for 10 quarts, up from $36 on May 30, according to Mizuho Securities.

From The Wall Street Journal ● Sep. 28, 2026

It was his idea to revamp his diet, cutting all sweets, processed foods and seed oils.

From Los Angeles Times ● Sep. 17, 2026

He said that Boss Fix, Steady Work, and Fast Luck oils were the most popular ones this time of year—he almost couldn’t keep them stocked.

From "Root Magic" by Eden Royce

The charity said the 13 birds had been collected and taken away to be cleaned but several other "partially oiled" birds were spotted and proved unable to be retrieved.

From BBC ● Jul. 2, 2026

In college, I found a treadle machine in an empty dorm room, oiled it and made a blouse and quilt.

From The Wall Street Journal ● May 2, 2026

When I finally nailed a roast chicken — buttered and oiled, stuffed with lemon wedges and hunks of onion and fennel — I felt like a goddess.

From Salon ● Dec. 20, 2025

Exterior walls, built from Douglas fir, were freshly oiled and flammable.

From Los Angeles Times ● Mar. 28, 2025

Words must be typed and driven into place, parts must be oiled.

From "The City Beautiful" by Aden Polydoros

I learned that oiling the blade prevents humidity from tarnishing the steel.

From The Wall Street Journal ● Nov. 23, 2025

The high concentration of pine forest in North Gyeongsang province, where the fires are burning, is also "oiling" the blaze, said a forest disaster expert.

From BBC ● Mar. 27, 2025

LeBron James oiling the offense like a 48-oz. can of WD-40.

From Los Angeles Times ● Apr. 14, 2023

If commoners' living standards slip—not relative to the elites, but relative to what they had before—they accept the overtures of the counter-elites and start oiling the axles of their tumbrels.

From Salon ● Jan. 9, 2023

She visualized the mother braiding it, her fingers oiling it with pomade before dividing it into sections with a wooden comb.

From "Half of a Yellow Sun" by Chimamanda Ngozi Adichie

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