[ ahyn-stahy-nee-uhm ]

nounChemistry, Physics.
  1. a transuranic element. Symbol: Es; atomic number: 99.

Origin of einsteinium

1950–55; named after Albert Einstein; see -ium

Words Nearby einsteinium

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British Dictionary definitions for einsteinium


/ (aɪnˈstaɪnɪəm) /

  1. a metallic transuranic element artificially produced from plutonium. Symbol: Es; atomic no: 99; half-life of most stable isotope, 252 Es: 276 days

Origin of einsteinium

C20: New Latin, named after Albert Einstein

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Scientific definitions for einsteinium


[ īn-stīnē-əm ]

  1. A synthetic, radioactive metallic element of the actinide series that is usually produced by bombarding plutonium or another element with neutrons. It was first isolated in a region near the explosion site of a hydrogen bomb. Its longest-lived isotope is Es 254 with a half-life of 276 days. Atomic number 99; melting point 860°C. See Periodic Table.

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