Tan"ta*lum (?), n. [NL. So named on account of the perplexity and difficulty encounterd by its discoverer (Ekeberg) in isolating it. See Tantalus.] Chem.
A rare nonmetallic element found in certain minerals, as tantalite, samarskite, and fergusonite, and isolated as a dark powder which becomes steel-gray by burnishing. Symbol Ta. Atomic weight 182.0. Formerly called also tantalium.
© Webster 1913.