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An element of the rare earth family of metals. It has the atomic symbol Y, atomic number 39, and atomic weight 88.91. In conjunction with other rare earths, yttrium is used as a phosphor in television receivers and is a component of the yttrium-aluminum garnet (YAG) lasers.

A rare metal allied to cerium; symbol Y.

A metallic element discovered at Ytterby, in Sweden, whence it derives its name. It occurs in very minute quantities. In compounds it acts as a trivalent radicle. Symbol, Y; atomic weight, 89.

n. A very rare metal of a scaly texture and grayish-black colour.