What does argon mean?
Argon is a chemical element with the symbol Ar and atomic number 18, classified among the noble gases — the family of elements famous for their extreme reluctance to react with other substances. A colourless, odourless, tasteless gas, it constitutes roughly 0.93% of the Earth's atmosphere, making it by far the most abundant noble gas in the air we breathe. Its very inertness is its greatest practical asset: argon is widely used to shield hot metals during welding, to fill incandescent light bulbs and double-glazed windows, and to provide a protective atmosphere in manufacturing processes where ordinary air would cause unwanted reactions. Discovered in 1894 by Lord Rayleigh and William Ramsay, it was the first noble gas to be identified, and its name derives from the Greek 'argos', meaning idle or lazy — a fitting tribute to its chemical passivity. Though rarely encountered by name outside scientific and industrial settings, argon quietly underpins many everyday technologies.
nounA colourless, odourless, chemically inert gaseous element (symbol Ar, atomic number 18) that makes up about 0.93% of the Earth's atmosphere and belongs to the group of noble gases.
- The chemical element argon (symbol Ar, atomic number 18), a colourless, odourless noble gas used in welding, lighting, and insulation.
"The light bulb was filled with argon to prevent the filament from oxidising at high temperatures."
"Double-glazed windows are often filled with argon because its low thermal conductivity improves insulation."
"The welder shielded the molten metal with a stream of argon to keep oxygen away from the joint."
As a mass noun denoting a substance, argon normally has no plural. A plural such as 'argons' appears only in rare technical contexts counting separate samples or isotopic species.
"The laboratory catalogued several purified argons from different sources."
Argon got its name from the Greek word for 'lazy' — chemists literally called it 'the lazy one' because it refuses to react with almost anything.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of argon
The word argon was coined in the late 19th century, following the element's discovery in 1894 by British physicists Lord Rayleigh and William Ramsay, who isolated it from atmospheric air. The name comes from the Greek 'argos', meaning 'idle', 'inactive', or 'lazy' — chosen because the new gas refused to combine chemically with any other substance they tested. The Greek root 'argos' is itself related to 'ergon', meaning 'work', so argon shares a distant origin with English words such as energy, organ, surgery, and allergy, all of which trace back through Greek forms built on that same root.
How argon is actually used
Argon is a technical/scientific term used mainly in chemistry, physics, engineering, and industrial contexts; it is uncountable when referring to the substance generally. It carries no figurative or informal usage.
Easily confused with argon
Arson is the criminal act of deliberately setting fire to property, whereas argon is an inert chemical element; the two differ by only one letter.