(pə·lā′dē·əm) noun plural ·di·a (-dē·ə)
Any object considered essential to the safety of a community or organization; a safeguard. [<PALLADIUM]

(pə·lā′dē·əm) noun
A rare metallic element (symbol Pd, atomic number 46) resembling platinum and in the spongy state capable of absorbing hydrogen in large quantities. See PERIODIC TABLE. [<NL, after Pallas, an asteroid discovered contemporaneously with the element]

(pə·lā′dē·əm)
In Greek and Roman legend, a statue of Pallas Athena in Troy on the preservation of which the city depended for safety. [<L <Gk. palladion, neut. of palladios of Pallas (Athena)]