D defs.my
Entry 1 sense Webster, 1913

Yttrium

/ĭt'rēəm/ · Yt·tri·um · IPA /ˈɪtɹiːəm/
01 n. A rare metallic element of the boron-aluminium group, found in gadolinite and other rare minerals, and extracted as a dark gray powder. Sy…
  1. 1.
    A rare metallic element of the boron-aluminium group, found in gadolinite and other rare minerals, and extracted as a dark gray powder. Symbol Y. Atomic number 39. Atomic weight, 88.9.(Chem.)