ランタノイド

noun

lanthanide; lanthanoid

Chemical term for the series of 15 metallic elements from lanthanum to lutetium. Both 'lanthanide' and 'lanthanoid' are used in English; 'lanthanoid' is the IUPAC-preferred term.

• ランタノイドは周しゅう期き表ひょうの第だい3族ぞくに属ぞくする元げん素そ群ぐんです。

  The lanthanoids are a group of elements belonging to Group 3 of the periodic table.

• ランタノイド収しゅう縮しゅくは、原げん子し半はん径けいが予よ想そうよりも小ちいさくなる現げん象しょうです。

  The lanthanoid contraction is a phenomenon where atomic radii become smaller than expected.