atomic number 57, n.
a white soft metallic element that tarnishes readily; occurs in rare earth minerals and is usually classified as a rare earth
<noun.substance>
La atomic number 57 lanthanum
semantic pointers
hypernym
Word
a white soft metallic element that tarnishes readily; occurs in rare earth minerals and is usually classified as a rare earth
<noun.substance>
La atomic number 57 lanthanum