xenon

American  

[zee-non, zen-on] / ˈzi nɒn, ˈzɛn ɒn /

noun

Chemistry.

1. a heavy, colorless, chemically inactive, monatomic gaseous element used for filling radio, television, and luminescent tubes. Xe; 131.30; 54.

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xenon British  

/ ˈzɛnɒn /

noun

1. a colourless odourless gaseous element occurring in trace amounts in air; formerly considered inert it is now known to form compounds and is used in radio valves, stroboscopic and bactericidal lamps, and bubble chambers. Symbol: Xe; atomic no: 54; atomic wt: 131.29; valency: 0; density: 5.887 kg/m³; melting pt: –111.76°C; boiling pt: –108.0°C

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xenon Scientific  

/ zē′nŏn′ /

1. A colorless, odorless element in the noble gas group occurring in extremely small amounts in the atmosphere. It was the first noble gas found to form compounds with other elements. Xenon is used in lamps that make intense flashes, such as strobe lights and flashbulbs for photography. Atomic number 54; atomic weight 131.29; melting point −111.9°C; boiling point −107.1°C; density (gas) 5.887 grams per liter; specific gravity (liquid) 3.52 (−109°C).

2. See Periodic Table

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Etymology

Origin of xenon

1898; < Greek xénon, neuter of xénos strange ( see -on ²); name introduced by William Ramsay, the element's discoverer

Explanation

The chemical element xenon is a colorless, odorless gas. The Earth's atmosphere contains just a little bit of xenon. First isolated in 1898 by the same chemists who discovered neon and krypton, this rare element is known for its heaviness. Because it's so scarce, xenon is also expensive, and it's mainly used to create extremely bright, brief flashes of light in specialized equipment like flash lamps. The Greek root of xenon is xenos, "rare or strange."

Example Sentences

"According to current literature, there is no evidence that breathing in xenon improves performance in the mountains, and inappropriate use can be dangerous," the International Climbing and Mountaineering Federation said in a statement in January.

From BBC • May 21, 2025

One mile beneath a mountain in Italy, scientists at the Gran Sasso National Laboratory fill a particle detector with liquid xenon, hoping to observe evidence of dark matter.

From Salon • Dec. 26, 2024

The undefined “glitch” led to a drop in the electrical power that strips electrons from neutral xenon gas atoms and accelerates the resulting positive ions to produce thrust far more efficiently than chemical rockets.

From Science Magazine • Jun. 3, 2024

Recently, scientists have begun to investigate the possibility that charged xenon particles were removed from the atmosphere by the magnetic field.

From Science Daily • Apr. 24, 2024

Tanya’s’s got the only xenon disco laser light in Europe!

From "Black Swan Green" by David Mitchell