mesothorium

American  

[mez-oh-thawr-ee-uhm, -thohr-, mes-, mee-zoh-, -soh-] / ˌmɛz oʊˈθɔr i əm, -ˈθoʊr-, ˌmɛs-, ˌmi zoʊ-, -soʊ- /

noun

Chemistry.

1. one of two radioactive decay products of thorium, an isotope of radium or actinium.

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mesothorium British  

/ ˌmɛsəʊˈθɔːrɪəm /

noun

1. obsolete physics either of the two radioactive elements which are decay products of thorium. Mesothorium I is now called radium-228. Mesothorium II is now called actinium-228

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Example Sentences

Each tiny bottle contained about a millionth of a gram of radium, the same amount of mesothorium.

From Time Magazine Archive

The paint contained radium and mesothorium salts which continually shoot out Alpha, Beta, Gamma rays.

From Time Magazine Archive

From thorium minerals a body was separated called mesothorium, which was analogous to radium.

From Project Gutenberg

The greatly extended use of radium, together with the distinctly limited character of the world's known radium supplies, has led to some concern; and considerable investigation has been made of the possibilities of mesothorium as a substitute for radium in luminous paints.

From Project Gutenberg

Mesothorium, a by-product of the manufacture of thorium nitrate for gas mantles, is used as a substitute for radium in luminous paints and for therapeutic purposes.

From Project Gutenberg