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

This route brings people together, including me and my car enthusiast friends, who regularly go on these driving excursions — gas prices be damned.

From Los Angeles Times ● Aug. 13, 2026

A company spokesperson said it had been "advised by the HSE that they are no longer looking at our physical network as part of their investigation. The gas network remains safe and secure".

From BBC ● Aug. 13, 2026

The gas distribution firm SGN said an engineer arrived within 16 minutes of receiving a call from a member of public just after midnight on Sunday.

From BBC ● Aug. 13, 2026

I’m putting solar on my house, so I’m pretty excited about no longer buying gas and being able to drive for free!

From The Wall Street Journal ● Aug. 12, 2026

I do a U-turn and hit the gas.

From "The Bletchley Riddle" by Ruta Sepetys and Steve Sheinkin

"And the main driver for this warming -- as we know -- are the greenhouse gases", he said.

From Barron's ● Aug. 10, 2026

The phenomenon happens when fluids - in this case hot gases - slide past each other and cause small disturbances to grow into spiralling vortices.

From BBC ● Aug. 5, 2026

Detonation waves form through a fluid mechanical instability involving wave and vortex patterns in the flowing gases.

From Science Daily ● Aug. 4, 2026

And, similarly, in multiple proceedings, it ignored the benefits of reducing the emissions of greenhouse gases, including carbon dioxide, methane, and hydrofluorocarbons.

From Slate ● Aug. 2, 2026

Refrigerators in the 1920s were often appallingly risky because they used dangerous gases that sometimes leaked.

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

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

The pyrolysis plants - often in rural backwaters - are akin to homemade pressure cookers and produce dangerous gasses and chemicals.

From BBC ● Mar. 25, 2025

Approaches like Graphyte’s nondescript beige blocks seem to be effective at preventing greenhouse gasses that would otherwise go into the atmosphere, and there seem to be multiple sustainable sources for such biomass too, she argues.

From Salon ● Jul. 18, 2024

The regulator analyzes the air with spectroscopy, then separates the gasses by supercooling them.

From "The Martian" by Andy Weir

Morris’s mother and father, respectively, were an accomplished organist and a mechanic who had been gassed in World War I. Like Waugh, Morris boarded as a teenager at Lancing College in West Sussex, England.

From The Wall Street Journal ● Apr. 23, 2026

“We were gassed the first time because that was right after we played Loyola,” Mustangs setter Jake Newman said.

From Los Angeles Times ● Apr. 21, 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 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

Whatever they gassed us with, it had to be simulation- inducing or I wouldn’t be the only one awake.

From "Insurgent" by Veronica Roth

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

You’re onstage every night, people gassing you up — And if you’re not self-aware, that’ll just keep stacking up until your ego’s huge and you’re not the same person you were.

From Los Angeles Times ● Aug. 6, 2025

Last week, the UN's High Commissioner for Human Rights urged a halt to the execution, saying that gassing Smith could amount to torture or other cruel, inhuman or degrading treatment under international human rights law.

From BBC ● Jan. 25, 2024

In the morning, after gassing up, I headed straight west along the Rainy River, which separates Minnesota from Canada, and which for me separated one life from another.

From "The Things They Carried" by Tim O'Brien

Related Words

• smoke
• vapor