a metallic transuranic element artificially produced from plutonium. Symbol: Es; atomic no: 99; half-life of most stable isotope, 252Es: 276 days
Word origin
C20: New Latin, named after Albert Einstein
einsteinium in American English
(aɪnˈstaɪniəm)
US
noun
a radioactive, metallic chemical element, one of the actinides, discovered in the debris of the first thermonuclear explosion in 1952, but now produced by bombarding plutonium with neutrons: symbol, Es; at. no., 99
Word origin
ModL, after Einstein2 (in honor of his theoretical studies of mass and energy) + -ium: so named (1955) by A. Ghiorso and co-workers, who identified it