a radioactive, metallic chemical element, one of the actinides, produced by intense neutron bombardment of plutonium, as in a cyclotron: symbol, Fm; at. no. 100
Origin of fermiumModL: so named (1955) by A. Ghiorso and co-workers, after E. Fermi (in honor of his studies in nuclear physics) + -ium
A synthetic transuranic metallic element having over 20 isotopes and isomers with mass numbers ranging from 242 to 260. The longest-lived isotope has mass number 257 and a half-life of approximately 100 days. Atomic number 100; melting point 1527°C; valence 3. See Periodic Table.
Origin of fermiumAfter Enrico Fermi.
- A transuranic chemical element (symbol Fm) with an atomic number of 100.
Named for Enrico Fermi.