radon

[rey-don]

noun

Chemistry.

1. a chemically inert, radioactive gaseous element produced by the decay of radium: emissions produced by outgassing of rock, brick, etc. are a health hazard. Rn; 86; 222.

radon

/ ˈreɪdɒn /

noun

1. a colourless radioactive element of the rare gas group, the most stable isotope of which, radon-222, is a decay product of radium. It is used as an alpha particle source in radiotherapy. Symbol: Rn; atomic no: 86; half-life of ²²² Rn: 3.82 days; valency: 0; density: 9.73 kg/m³; melting pt: –71°C; boiling pt: –61.7°C

radon

1. A colorless, odorless, radioactive element in the noble gas group. It is produced by the radioactive decay of radium and occurs in minute amounts in soil, rocks, and the air near the ground. Radon is used as a source of radiation for the treatment of cancer and other diseases. Its most stable isotope is Rn 222 with a half-life of 3.82 days. Atomic number 86; melting point −71°C; boiling point −61.8°C; specific gravity (solid) 4.

2. See Periodic Table

radon

1. A colorless, odorless, radioactive gas that is produced by the decay of radium in the soil.

Radon seeping through the ground and into buildings is a major source of indoor air pollution and may represent a significant risk for lung cancer.

Word History and Origins

Origin of radon¹

First recorded in 1915–20; rad(ium) + -on ²

Word History and Origins

Origin of radon¹

C20: from _radium + _-on

Example Sentences

It contains radium that decays into radon gas, which is radioactive and can cause cancer.

Read more on Barron's

The department said it followed the discovery of high levels of radon at the jail.

Read more on BBC

Doctors say this concerning rise in non-smoking lung cancer cases is likely linked to long-term, high exposures of radon gas.

Read more on Science Daily

The BBC understands no prisoners or staff have reported becoming ill or suffering an adverse reaction to radon exposure at the jail.

Read more on BBC

The study does not prove that exposure to radon causes stroke; it only shows an association.

Read more on Science Daily