mesothorium
[ mez-oh-thawr-ee-uh m, -thohr-, mes-, mee-zoh-, -soh- ]
/ ˌmɛz oʊˈθɔr i əm, -ˈθoʊr-, ˌmɛs-, ˌmi zoʊ-, -soʊ- /
noun Chemistry.
one of two radioactive decay products of thorium, an isotope of radium or actinium.
Nearby words
mesotendineum, mesothelioma, mesothelium, mesotherapy, mesothorax, mesothorium, mesotron, mesovarium, mesozoa, mesozoan, mesozoic
Dictionary.com Unabridged
Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
British Dictionary definitions for mesothorium
mesothorium
/ (ˌmɛsəʊˈθɔːrɪəm) /
noun
physics obsolete 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
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
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