[ noun ] a silvery metallic element that is common in rare-earth minerals; used in magnesium and aluminum alloys <noun.substance>
Yttrium \Yt"tri*um\, n. [NL., from Ytterby, in Sweden. See {Erbium}.] (Chem.) 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. [Written also {ittrium}.] [1913 Webster +PJC]
Note: Associated with yttrium are certain rare elements, as erbium, ytterbium, samarium, etc., which are separated in a pure state with great difficulty. They are studied by means of their spark or phosphorescent spectra. Yttrium is now regarded as probably not a simple element, but as a mixture of several substances.
The wire, one-eighth-inch in diameter, is based on a standard superconducting compound of yttrium, barium, copper and oxygen.
Last year, scientists in both Japan and the U.S. developed crystals of zirconium and yttrium oxides that are moldable at 1,150 degrees Celsius and might be used in 500-degree applications.