discovered in the debris of a 1952 U.S. nuclear test in the Pacific, named 1955 for Italian-born U.S. physicist Enrico Fermi (1901-1954).
fermium fer·mi·um (fûr'mē-əm, fěr'-)
A synthetic radioactive metallic element whose most stable isotope is Fm 257 with a half-life of [approx] 100 days. Atomic number 100.
A synthetic, radioactive metallic element of the actinide series that is produced from plutonium or uranium. Its most stable isotope is Fm 257 with a half-life of approximately 100 days. Atomic number 100. See Periodic Table.