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noun
Certain members of the decay chain of thorium, mainly isotopes of radium and actinium
Definition source: English Wiktionary via Wiktextract
Topics: natural-sciences, physical-sciences, physics
No example sentence was provided for this meaning.
Synonyms: none provided
Antonyms: none provided
History
From meso- + thorium. Probably so-called because these two isotopes (228Ra and 228Ac) are, in the decay chain, intermediate between normal thorium (232Th) and radiothorium (228Th).
Across languages
1 source translations are retained for this English entry.
