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

For example, a “new element” produced by the radioactive decay of thorium was initially given the name mesothorium.

From Textbooks • Feb. 14, 2019

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

From Time Magazine Archive

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

From Time Magazine Archive

Radium, mesothorium, and the roentgenray are reported to have had in certain isolated cases a seemingly beneficial action.

From Bronchoscopy and Esophagoscopy A Manual of Peroral Endoscopy and Laryngeal Surgery by Jackson, Chevalier

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

From A Brief Account of Radio-activity by Venable, Francis Preston