Ytterbium
Pronunciation : Yt*ter"bi*um
Part of Speech : n.
Etymology : [NL., fr. Ytterby, in Sweden. See Erbium.] (Chem.)
Definition : Defn: 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.
Note: Ytterbium is associated with other rare elements, and probably has not been prepared in a pure state.
Source : Webster's Unabridged Dictionary, 1913