Noun: thorium tho-ree-um
- 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
"Thorium is being researched as a potential nuclear fuel"; "Thorium, atomic number 90, is being researched as a potential nuclear fuel";
- Th, atomic number 90
Derived forms: thoriums
Type of: metal, metallic element
Encyclopedia: Thorium