ionium

American  

[ahy-oh-nee-uhm] / aɪˈoʊ ni əm /

noun

Chemistry.

1. a naturally occurring radioactive isotope of thorium. Io; 90; 230.

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ionium British  

/ aɪˈəʊnɪəm /

noun

1.  Io.  obsolete a naturally occurring radioisotope of thorium with a mass number of 230

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Etymology

Origin of ionium

First recorded in 1905–10; ion + -ium

Example Sentences

She also proved that a recently discovered element – ionium – didn’t exist.

From Nature

Rona’s new job was to isolate “ionium,” a mysterious substance that was suspectedof being new element.

From Salon

Unlike those that had failed before her, Rona proved “ionium” was simply an isotope of thorium.

From Salon

So, too, he makes us realise, with a quickening and expanding emotion, which seems to bring us nearer to the core of Nature, the majesty of the sea breaking on a great expanse of shore,—the solemn stillness of midnight,—the invisible agency by which the clouds form the pageantry of the sky,—the active noiseless energy by which rivers wear away their banks,—by the use of words that seem exactly equivalent to the thing which they describe,— Quam fluitans circum magnis anfractibus aequor Ionium glaucis aspargit virus ab undis10.

From Project Gutenberg

Then crusty old Elias Loomis pioneered in devising the basis for modern weather maps and Bertram Boltwood discovered ionium.

From Time Magazine Archive