\Er"bi*um\, n. [NL. from Ytterby, in Sweden, where
gadolinite is found. Cf. {Terbium}, {Yttrium}, {Ytterbium}.]
(Chem.)
A rare metallic element associated with several other rare
elements in the mineral gadolinite from Ytterby in Sweden.
Symbol Er. Atomic weight 165.9. Its salts are rose-colored
and give characteristic spectra. Its sesquioxide is called
erbia.

\Er"bi*um\, n. [NL. Named from Ytterby, in Sweden, where
gadolinite is found. Cf. {Terbium}, {Yttrium}, {Ytterbium}.]
(Chem.)
A metallic element of the rare earth group, found in
gadolinite and some other minerals. Symbol, Er; at. wt.
167.4. Its salts are rose-colored and give characteristic
spectra.