Synonyms/Hypernyms (Ordered by Estimated Frequency) of noun thorium-228
1 sense of thorium-228
Sense 1
thorium-228, radiothorium -- (radioactive isotope of thorium with mass number 228)
=> thorium, Th, atomic number 90 -- (a soft silvery-white tetravalent radioactive metallic element; isotope 232 is used as a power source in nuclear reactors; occurs in thorite and in monazite sands)