'Europium' definitions:

Definition of 'europium'

From: WordNet
noun
A bivalent and trivalent metallic element of the rare earth group [syn: europium, Eu, atomic number 63]

Definition of 'Europium'

From: GCIDE
  • Europium \Eu*ro"pi*um\, n. [NL.; Europe + -ium, as in aluminium.] (Chem.) A metallic element of the rare-earth group (Lanthanide series), discovered spectroscopically by Demarcay in 1896. Symbol, Eu; atomic number 63; at. wt., 151.965 (C=12.011); valence = +2 or +3. [Webster 1913 Suppl. +PJC]

Definition of 'Europium'

From: Elements
  • Symbol: Eu
  • Atomic number: 63
  • Atomic weight: 151.25
  • Soft silvery metallic element belonging to the lanthanoids. Eu-151 and Eu-153 are the only two stable isotopes, both of which are neutron absorbers. Discovered in 1889 by Sir William Crookes.