argon

American  

[ahr-gon] / ˈɑr gɒn /

noun

Chemistry.

1. a colorless, odorless, chemically inactive, monatomic, gaseous element that, because of its inertness, is used for filling fluorescent and incandescent lamps and vacuum tubes. Ar; 18; 39.948.

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argon British  

/ ˈɑːɡɒn /

noun

1. an extremely unreactive colourless odourless element of the rare gas series that forms almost 1 per cent (by volume) of the atmosphere. It is used in electric lights. Symbol: Ar; atomic no: 18; atomic wt: 39.948; density: 1.7837 kg/m³; freezing pt: –189.3°C; boiling pt: –185.9°C

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argon Scientific  

/ är′gŏn′ /

1. A colorless, odorless element in the noble gas group. Argon makes up about one percent of the atmosphere. It is used in electric light bulbs, fluorescent tubes, and radio vacuum tubes. Atomic number 18; atomic weight 39.948; melting point −189.2°C; boiling point −185.7°C.

2. See Periodic Table

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Etymology

Origin of argon

1890–95; < Greek, neuter of argós inactive, not working, idle, contraction of aergós equivalent to a- a- ⁶ + érg ( on ) work + -os adj. suffix

Example Sentences

His frame is lit from within, head-to-toe, by argon trapped in electrified tubes shaped to resemble the human circulatory system, making his soul visible.

From Los Angeles Times • Oct. 16, 2025

Earth’s atmosphere is a blend of nitrogen, oxygen, argon and other gases.

From Seattle Times • May 8, 2024

To date the ice, Sarah Shackleton, a paleoclimatologist at the Woods Hole Oceanographic Institution, and her team analyzed the argon isotopes contained in its air bubbles.

From Science Magazine • Apr. 21, 2024

They found light from atoms of the elements, argon and sulphur that could have only been produced by powerful radiation coming from a neutron star at the centre of the supernova.

From BBC • Feb. 23, 2024

Its air is thin, containing mostly carbon dioxide but also some molecular nitrogen and argon and very small quantities of water vapor, oxygen and ozone.

From "Cosmos" by Carl Sagan