Plural of “gas”

The plural of gas is gases.

Why

"Gas" was coined in the early 17th century by the Flemish chemist Jan Baptista van Helmont, who invented the word deliberately, possibly influenced by the Greek word "chaos," to describe substances that expanded freely to fill any container, unlike liquids or solids. As a modern scientific coinage rather than an inherited word, it follows the regular English rule for short words ending in a single s after a short vowel, adding -es to give "gases."

Van Helmont's invented word is one of relatively few English nouns with a documented single inventor and an exact approximate coining date, unlike most vocabulary, which develops gradually and anonymously over centuries; that clear, deliberate scientific origin meant the word entered English fully formed, with its plural settling immediately into ordinary spelling conventions rather than following any older or borrowed pattern.

Usage note

"Gases" is the standard plural in scientific, technical, and everyday writing alike ("greenhouse gases," "noble gases"); "gasses" does appear as a variant spelling, mostly as the third-person singular verb form ("the compound gasses off slowly") rather than as the noun plural.

Van Helmont was a pioneering early chemist who helped establish foundational experimental methods of modern chemistry, and his coinage of "gas" reflected his interest in classifying matter more precisely than the traditional four-element system that had dominated Western science since antiquity. Modern chemistry and environmental science rely on "gases" constantly as a precise technical plural, from "greenhouse gases" in climate science to "noble gases" in the periodic table.

Common real mistakes

The main slip is confusing the noun plural "gases" with the verb form "gasses," which describes the action of releasing gas rather than naming multiple gases as substances — a distinction that matters most in technical and scientific writing where precision counts. American English also uses "gas" informally as shorthand for "gasoline," an uncountable mass-noun sense entirely distinct from the countable scientific sense discussed here, and this informal sense essentially never pluralizes at all.

The wider pattern

"Gas" pluralizes the same way as "bus," both being short words ending in a single s after a short vowel that take -es in the plural, though "gas" has the added distinction of being one of the very few English nouns whose invention by a specific named individual is genuinely documented history rather than etymological guesswork.

Examples

• The lab tested several gases for flammability.
• Greenhouse gases trap heat within the earth's atmosphere.
• Noble gases are known for their chemical stability.
• The facility stores various industrial gases in pressurized tanks.
• Volcanic eruptions release enormous quantities of gases.
• Engineers monitor gases within the reactor around the clock.
• Certain gases are heavier than air and settle near the ground.
• The chemistry class studied how gases expand when heated.
• Toxic gases forced the evacuation of the building.
• Researchers measured atmospheric gases at varying altitudes.
• The plant captured waste gases before they reached the atmosphere.
• Divers carry mixed gases for deep underwater expeditions.
• The pipeline transports natural gases across three states.
• Chemists compared how different gases behave under pressure.
• Regulators set new limits on industrial gases released into the air.
• The tank held a mixture of gases used for welding.
• Refineries process crude oil into a range of usable gases.
• The experiment measured how gases diffuse at different temperatures.
• The mine was evacuated after gases were detected underground.
• Chefs use specific gases to keep produce fresh longer.
• The satellite measured gases in the upper atmosphere.
• The utility company inspected pipelines carrying natural gases.
• Students measured how gases expand when heated in the lab.
• The greenhouse monitored gases to optimize plant growth.
• The lab safely vented the gases after the experiment.
• Engineers tested how the gases reacted under high pressure.