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

Oil companies are enjoying a profit boom driven by high prices for gas and diesel fuel.

From The Wall Street Journal ● Sep. 2, 2026

Amazon’s robotaxi effort Zoox, which utilizes a purpose-built vehicle with no steering wheel or gas pedal, started charging for its first paid rides in Las Vegas last month.

From Los Angeles Times ● Sep. 2, 2026

It does not include nonradiative effects such as collisions and drag from interstellar gas or dust.

From Science Daily ● Sep. 2, 2026

But to achieve this, carbon dioxide removal -- the process of pulling carbon from the air -- would be required at enormous scale alongside major, rapid cuts to greenhouse gas emissions, the report said.

From Barron's ● Sep. 2, 2026

His face is undecipherable; it’s covered by a green rubber gas mask.

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

Press reports indicated Elliott has taken a stake in the French supplier of industrial gases.

From The Wall Street Journal ● Sep. 2, 2026

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

The felt surrounds the 3D-printed restoration and gives gases released by the resin a way to escape.

From Science Daily ● Aug. 23, 2026

However, there are still significant challenges, from releasing potentially dangerous gases locked in the ground to occasional flooding issues.

From BBC ● Aug. 18, 2026

No one knew what would happen if their very hot exhaust gases touched my suit.

From "Flying to the Moon: An Astronaut's Story" by Michael Collins

It is thought the premises in Cresswell Crescent were being refurbished and a generator released toxic gasses.

From BBC ● Sep. 28, 2025

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

"Current scientific models in the presence of ongoing rises in atmospheric greenhouse gasses do not predict this threatening acceleration," Professor Smith said.

From Science Daily ● Nov. 26, 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

“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

He was also making his 11th appearance of the postseason, only days removed from a rocky Game 2 outing in which he looked gassed.

From Los Angeles Times ● Nov. 1, 2024

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

"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

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

“Everyone is gassing each other up about how fabulous they look,” she says.

From Los Angeles Times ● May 13, 2025

But Ella's family didn't believe in gassing you up.

From "The Marvellers" by Dhonielle Clayton

Related Words

• smoke
• vapor