Ythrowe
Y•throwe´, obs. p. p. of Throw. Chaucer.

Ytterbic
Yt•ter´bic, a. (Chem.) Pertaining to, or derived from, ytterbium; containing ytterbium.

Ytterbium
Yt•ter´bi•um, n. [NL., fr. Ytterby, in Sweden. See Erbium.] (Chem.) A rare element of the boron group, sometimes associated with yttrium or other related elements, as in euxenite and gadolinite. Symbol Yb; provisional atomic weight 173.2. Cf. Yttrium. Ytterbium is associated with other rare elements, and probably has not been prepared in a pure state.

Yttria
Yt´tri•a, n. [NL. See Yttrium.] (Chem.) The oxide, Y₂O₃, or earth, of yttrium.

Yttric
Yt´tric, a. (Chem.) Pertaining to, derived from, or containing, yttrium.

Yttriferous
Yt•trif´er•ous, a. Bearing or containing yttrium or the allied elements; as gadolinite is one of the yttriferous minerals.

Yttrious
Yt´tri•ous, a. (Chem.) Same as Yttric.

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 weight, 89. [Written also ittrium.] 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.

Yttro-cerite
Yt•tro-ce´rite, n. (Min.) A mineral of a violet-blue color, inclining to gray and white. It is a hydrous fluoride of cerium, yttrium, and calcium. { Yt•tro-co•lum´bite, Yt•tro-tan´ta•lite, } n. (Min.) A tantalate of uranium, yttrium, and calcium, of a brown or black color.