The chemical element of atomic number 100, a radioactive metal of the actinide series. Fermium does not occur naturally and was discovered in 1953 in the debris of the first hydrogen bomb explosion. (Symbol: Fm)
More example sentences
- Scientists have for the first time literally shed light on properties of the radioactive element fermium - a metal discovered some 50 years ago.
- All isotopes of fermium are radioactive, with fermium-257 having the longest half life, 20.1 hours.
- The transfermium elements are those elements with atomic numbers greater than 100, the atomic number for fermium.
Definition of fermium in:
- The US English dictionary