curium cu·ri·um (kyur'ē-əm)
A metallic synthetic radioactive transuranic element. Atomic number 96; longest-lived isotope Cm 247; melting point (estimated) 1,350°C; valence 3,4.
A synthetic, silvery-white, radioactive metallic element of the actinide series that is produced artificially from plutonium or americium. Curium isotopes are used to provide electricity for satellites and space probes. Its most stable isotope has a half-life of 16.4 million years. Atomic number 96; melting point (estimated) 1,350°C; valence 3. See Periodic Table.