Yraft
(Y*raft") obs. p. p. of Reave. Bereft. Chaucer.
Yren
(Yr"en) n. Iron. [Obs.] Chaucer.
Yronne
(Y*ron"ne) obs. p. p. of Run. Run. Chaucer.
Ysame
(Y*same") adv. [See Same.] Together. [Obs.] "And in a bag all sorts of seeds ysame." Spenser.
Yt
(Yt, Yt) (&thligat), an old method of printing that (AS. þæt, ðæt) the "y" taking the place of the old letter
"thorn" Cf. Ye, the.
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.
Yttro-columbite
(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.
Yu
(||Yu) n. [Chin.] (Min.) Jade.
Yucca
(Yuc"ca) n. (Zoöl.) See Flicker, n., 2.
Yucca
(||Yuc"ca) n. [NL., from Yuca, its name in St. Domingo.] (Bot.) A genus of American liliaceous,
sometimes arborescent, plants having long, pointed, and often rigid, leaves at the top of a more or less
woody stem, and bearing a large panicle of showy white blossoms.
The species with more rigid leaves (as Yucca aloifolia, Y. Treculiana, and Y. baccata) are called Spanish
bayonet, and one with softer leaves (Y. filamentosa) is called bear grass, and Adam's needle.
Yucca moth (Zoöl.), a small silvery moth (Pronuba yuccasella) whose larvæ feed on plants of the genus
Yucca.
