\Scan"di*um\, n. [NL. So called because found in Scandinavian minerals.] (Chem.) A rare metallic element of the boron group, whose existence was predicted under the provisional name {ekaboron} by means of the periodic law, and subsequently discovered by spectrum analysis in certain rare Scandinavian minerals (euxenite and gadolinite). It has not yet been isolated. Symbol Sc. Atomic weight 44.