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

The worst natural gas leak in the nation’s history happened in 2015 in Aliso Canyon, and 11,000 people were evacuated from their Porter Ranch homes.

From Los Angeles Times ● Jul. 15, 2026

At the heart of the resumption of hostilities has been the dispute over the Strait of Hormuz, a waterway that is crucial for global oil and gas flows.

From Barron's ● Jul. 15, 2026

The challenge could intensify as the EU phases out Russian LNG and pipeline gas contracts, leaving buyers with fewer options.

From The Wall Street Journal ● Jul. 15, 2026

“It plays well with voters in general, not just because of the dominance of oil and natural gas in Texas, but just because of the political makeup of our state,” Longanecker said.

From Salon ● Jul. 15, 2026

I didn’t want to face Rae Ellen inside the store, so I waited outside on the sagging bench near the gas pumps.

From "The Seven Wonders of Sassafras Springs" by Betty G. Birney

“That refusal forces victims to pay their own way out, and leaves those who can’t afford to leave trapped in gases and toxins that no agency will name.”

From Los Angeles Times ● Jul. 14, 2026

China is the world's biggest emitter of greenhouse gases, but it is also a global renewable energy powerhouse that aims to make its massive economy carbon-neutral by 2060.

From Barron's ● Jul. 7, 2026

To determine what happens to these chemicals during fireworks displays, researchers measured amines in both gases and airborne particles during Lunar New Year celebrations in a suburban area of China.

From Science Daily ● Jul. 4, 2026

It will produce liquid ammonia—a chemical widely used in fertilizer—from hydrogen and nitrogen gases.

From The Wall Street Journal ● Jul. 2, 2026

The reaction vessel is initially transparent: the precursor gases are entirely invisible.

From "Cosmos" by Carl Sagan

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

These gasses trap heat in the atmosphere, contributing to rising temperatures.

From Los Angeles Times ● Oct. 16, 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

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

The format brought new energy and understanding into their catalogs, all while the pair gassed each other up as virtuoso live performers.

From Los Angeles Times ● May 22, 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

In addition, the method used to kill the infected chickens — carbon dioxide gassing — required that workers move “from chicken to chicken” increasing their “degree of interaction with each potentially infected bird.”

From Los Angeles Times ● Jul. 16, 2024

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

They idled at a stoplight, and Kendra stared at an overweight woman gassing up her minivan.

From "Fablehaven" by Brandon Mull

Related Words

• smoke
• vapor