thoron

[thawr-on, thohr-]

noun Chemistry.

a radioactive isotope of radon, produced by the disintegration of thorium. Symbol: Tn; atomic weight: 220; atomic number: 86.

Origin of thoron

First recorded in 1925–30; thor(ium) + -on²

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Examples from the Web for thoron

Historical Examples of thoron

But the crusaders embarrassed themselves with the siege of the castle of Thoron.
The History of Chivalry
G. P. R. James

British Dictionary definitions for thoron

thoron

noun

a radioisotope of radon that is a decay product of thorium. Symbol: Tn or 220 Rn; atomic no: 86; half-life: 54.5s

Word Origin for thoron

C20: from thorium + -on

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