gas

American  

[gas] / gæs /

noun

• gases,
  plural
• gasses
  plural

1. Physics. a substance possessing perfect molecular mobility and the property of indefinite expansion, as opposed to a solid or liquid.

2. any such fluid or mixture of fluids.

3. any such fluid used as an anesthetic, as nitrous oxide.

   Did the dentist give you gas for your extraction?

4. any such combustible fluid used as fuel.

   Light the gas in the oven.

5. Automotive.

   1. gasoline.

   2. Also called gas pedal. the foot-operated accelerator of an automotive vehicle.

      Take your foot off the gas.

6. flatus.

7. Coal Mining. an explosive mixture of firedamp with air.

8. an aeriform fluid or a mistlike assemblage of fine particles suspended in air, used in warfare to asphyxiate, poison, or stupefy an enemy.

9. Slang.

   1. empty talk.

   2. a person or thing that is very entertaining, pleasing, or successful.

      The party was an absolute gas, and we loved it.

   3. a person or thing that affects one strongly.

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verb (used with object)

• gasses,
  present (3rd person singular)
• gassed,
  past participle,  past
• gassing
  present participle

1. to supply with gas.

2. to overcome, poison, or asphyxiate with gas or fumes.

3. to singe (yarns or fabrics) with a gas flame to remove superfluous fibers.

4. to treat or impregnate with gas.

5. Slang.

   1. to talk nonsense or falsehood to.

   2. to amuse or affect strongly.

      Her weird clothes really gas me.

verb (used without object)

• gasses,
  present (3rd person singular)
• gassed,
  past participle,  past
• gassing
  present participle

1. to give off gas, as a storage battery being charged.

2. Slang.

   1. to indulge in idle, empty talk.

   2. to become drunk (often followed byup ).

verb phrase

1. gas up to fill the gasoline tank of an automobile, truck, or other vehicle.

idioms

1. step on the gas, to increase the speed of one's movement or activity; hurry.

   We'd better step on the gas or we'll be late for the concert.

gas British  

/ ɡæs /

noun

1. a substance in a physical state in which it does not resist change of shape and will expand indefinitely to fill any container. If very high pressure is applied a gas may become liquid or solid, otherwise its density tends towards that of the condensed phase Compare liquid solid

2. any substance that is gaseous at room temperature and atmospheric pressure

3. any gaseous substance that is above its critical temperature and therefore not liquefiable by pressure alone Compare vapour

4. 1. a fossil fuel in the form of a gas, used as a source of domestic and industrial heat See also coal gas natural gas

   2. ( as modifier )

      a gas cooker

      gas fire

5. a gaseous anaesthetic, such as nitrous oxide

6. mining firedamp or the explosive mixture of firedamp and air

7. the usual US, Canadian, and New Zealand word for petrol See also gasoline

8. informal

   1. to increase the speed of a motor vehicle; accelerate

   2. to hurry

9. a toxic or suffocating substance in suspension in air used against an enemy

10. informal idle talk or boasting

11. slang a delightful or successful person or thing

    his latest record is a gas

12. an informal name for flatus

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verb

1. (tr) to provide or fill with gas

2. (tr) to subject to gas fumes, esp so as to asphyxiate or render unconscious

3. (intr) to give off gas, as in the charging of a battery

4. (tr) (in textiles) to singe (fabric) with a flame from a gas burner to remove unwanted fibres

5. informal to talk in an idle or boastful way (to a person)

6. slang (tr) to thrill or delight

gas Scientific  

/ găs /

1. One of four main states of matter, composed of molecules in constant random motion. Unlike a solid, a gas has no fixed shape and will take on the shape of the space available. Unlike a liquid, the intermolecular forces are very small; it has no fixed volume and will expand to fill the space available.

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gas Cultural  

1. In physics, one of the phases of matter. The atoms or molecules in gases are more widely spaced than in solids or liquids and suffer only occasional collisions with one another.

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gas More Idioms  

More idioms and phrases containing gas

• cook with gas
• run out of steam (gas)

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Other Word Forms

Derived Forms

• nongas
  noun
• gasless
  adjective

Inflected Forms

Nouns

• gases
  plural
• gasses
  plural

Participles

• gassing
  present
• gassed
  past

Conjugated Forms

Present

• gas
  simple
• gasses
  simple
• have gassed
  perfect
• has gassed
  perfect
• am gassing
  progressive
• are gassing
  progressive
• is gassing
  progressive
• have been gassing
  perfect progressive
• has been gassing
  perfect progressive

Past

• gassed
  simple
• had gassed
  perfect
• was gassing
  progressive
• were gassing
  progressive
• had been gassing
  perfect progressive

Future

• will gas
  simple
• will have gassed
  perfect
• will be gassing
  progressive
• will have been gassing
  perfect progressive

Etymology

Origin of gas

First recorded in 1650–60; coined by J. B. van Helmont (1577–1644), Flemish chemist; suggested by Greek cháos “atmosphere”

Explanation

Matter can be found in solid, liquid, or gas form. The air you breathe in and the carbon dioxide you breathe out, are both examples of gas. Gasoline is a kind of a gas that you use as car fuel, and when people say they need gas, usually this is the kind they're talking about. They're probably not talking about the digestive kind of gas that causes you to fart. There are poisons that can be released as gas, and you might hear about riot police somewhere gassing people: spraying them with harmful gas. Gas has no fixed shape and changes density easily.

Example Sentences

See Examples For:

gas gases gasses gassed gassing

European Union gas storage facilities are around 73% full, according to industry group Gas Infrastructure Europe, well below the five-year average of 89%.

From The Wall Street Journal ● Oct. 13, 2026

Linde is securing multiyear gas supply contracts that are essential to advanced semiconductor fabrication.

From Barron's ● Oct. 13, 2026

Cadent is keeping a road closure in place on Great Winchester Street while engineers complete repairs to the damaged gas pipeline.

From BBC ● Oct. 13, 2026

Send your favorite money tip for saving on anything from gas and groceries to plane tickets to [email protected], and we’ll share it in next week’s newsletter.

From MarketWatch ● Oct. 13, 2026

How could a ball of gas a billion miles away in space be able to do that?

From "The Way to Rio Luna" by Zoraida Cordova

"Since the incident we have learnt lessons, and as part of this, we have improved our oversight of the monitoring of medical gases across the maternity unit at Basildon Hospital."

From BBC ● Oct. 13, 2026

The French industrial gases supplier expects M&A to contribute around one percentage point of its 5% sales compound annual growth rate target, primarily through bolt-ons.

From The Wall Street Journal ● Oct. 9, 2026

But fabrication and assembly plant workers can face exposure to solvents, acids, toxic metals and chemical gases, according to the US Occupational Safety and Health Administration.

From Barron's ● Oct. 7, 2026

Both conventional and botanical cleaning products generated complex multiphase exposure scenarios involving reactive gases and secondary organic aerosol.

From Science Daily ● Sep. 26, 2026

Thus copper sits on top of silver and silver sits on top of gold because of their chemical affinities as metals, while helium, neon, and argon are in a column made up of gases.

From "A Short History of Nearly Everything" by Bill Bryson

The industrial gasses company said Monday that it wants to grow net earnings per share by a compound annual growth rate of 10% over the period, from the 6.1 euros it reported for 2025.

From The Wall Street Journal ● Oct. 5, 2026

The gas detected in the atmosphere is helium, which would not be able to support life, but other gasses may also be present.

From BBC ● Jul. 17, 2026

The flights will be used to conduct various studies and to sample atmospheric gasses and measure land and water surfaces.

From Los Angeles Times ● Jun. 27, 2025

Unlike visible light, radio waves from hot gasses are not blocked that easily by cosmic dust.

From Space Scoop ● Mar. 27, 2025

Ash and gasses once more jetted into the sky from Mount St. Helens.

From "Mountain of Fire" by Rebecca E. F. Barone

Fitness is next: He looked a little gassed against Zverev, and admitted as much.

From The Wall Street Journal ● Sep. 14, 2026

“I’m not sure why Taylor picked such a rundown place to film, but I’m gassed about it,” said Hogg, 24.

From The Wall Street Journal ● Mar. 5, 2026

He finished with eight points in his debut, shooting three of 15 from the perimeter in a performance that left him obviously gassed throughout.

From Los Angeles Times ● Jan. 22, 2026

He uploaded his first song, Plethora, to TiKTok in 2019 and was "gassed" when it received 1,000 plays in a day.

From BBC ● Jan. 8, 2026

This was of course after they had already gassed each other up, talking to each other like there was no one else on the track but them.

From "Patina" by Jason Reynolds

"From the first round, I saw his gassing out. He started fast. I knew he was going to gas out. I knew when my chance came I needed to push. That is what I did."

From BBC ● Aug. 29, 2026

The rest stop duration may require a bit more time than gassing up, and that is an added safety factor on a road trip.

From The Wall Street Journal ● Jul. 12, 2026

Some travelers say they can’t afford not to travel, however, so they’re putting all options on the table — from booking rail tickets to gassing up their cars.

From MarketWatch ● Nov. 8, 2025

The officers approached Castellano while he was gassing up his truck at a busy Safeway service station in Kirkland.

From Seattle Times ● Dec. 15, 2023

It's like he felt tougher whenever he started blabbing about it, gassing his own head up, turning the story into a much bigger deal than it really was.

From "When I Was the Greatest" by Jason Reynolds

Related Words

• smoke
• vapor