- noun a silvery-white metallic radioactive element in the actinide group artificially produced from plutonium
- A synthetic element whose atomic number is 96. It is a reactive silvery-white metal, and has about 20 known isotopes, all of which are unstable. It is used, for instance, for compact thermionic or thermoelectric power generation, especially for use in remote areas such as outer space. Its chemical symbol is Cm.
- chemical symbolCm