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

They took their proverbial foot off the gas, ran out of gas, sputtered to the finish line, got outscored 23-7 in the fourth quarter and looked like anything but a team with serious playoff plans.

From Los Angeles Times ● Aug. 30, 2026

"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

Scientists from ECU's School of Engineering found that magnetite can release hydrogen gas when it reacts with hot water under conditions similar to those deep below the Earth's surface.

From Science Daily ● Aug. 29, 2026

Natural gas is a critical input for nitrogen fertilizer, while oil refining and gas processing produce much of the sulfur needed for phosphate fertilizer.

From The Wall Street Journal ● Aug. 28, 2026

I watch as they emerge, ghostlike, from the shadows, clutching gas masks and items most dear to them.

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

They found that nearly half of those declines were caused by the planet-heating gases released into the atmosphere by 122 of the world’s largest fossil fuel and cement companies.

From Los Angeles Times ● Aug. 26, 2026

It has rather led to soaring commuter congestion, and “250,000 tons of additional greenhouse gases each year” as cars sit in traffic.

From The Wall Street Journal ● Aug. 26, 2026

Some hollow core fibers can be filled with gases or liquids, allowing them to map temperature distributions or even function as tiny laboratories for chemical experiments.

From Science Daily ● Aug. 22, 2026

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

From Barron's ● Aug. 10, 2026

When corn, oats, or sorghum containing large amounts of nitrates are ensiled they release poisonous nitrogen oxide gases, creating a deadly hazard to anyone entering the silo.

From "Silent Spring" by Rachel Carson

We found the defects can make the graphene more "sticky" to other materials, making it more useful as a catalyst, as well as improving its capability of detecting different gasses for use in sensors.

From Science Daily ● Dec. 4, 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

The WMO reports historically high levels of the greenhouse gasses methane and nitrous oxide, which like carbon dioxide are common byproducts of human industry.

From Salon ● Oct. 31, 2024

The regulator uses freeze-separation to sort out the gasses.

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

“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

While showing few outward signs of struggling with the foot blisters which troubled him in the quarter-finals, Djokovic regularly looked gassed against Sinner before finding further reserves to win in four hours and nine minutes.

From BBC ● Jan. 31, 2026

They couldn’t lean on Ohtani, who looked gassed while starting the game as a pitcher on short rest.

From Los Angeles Times ● Nov. 4, 2025

I was psyched, I'm talking totally gassed about this.

From "Patina" by Jason Reynolds

Charging may require a bit more time than gassing up, but it’s a chance to catch up on news and email.

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