zirconium
Cross references: 1. element zir.co.ni.um \.z*r-'ko--ne--*m\ n [NL, fr. ISV zircon] : a steel-gray strong ductile chiefly tetravelent metallic element with a high melting point that occurs widely in combined form esp. in zircon, is highly resistant to corrosion, and is used in alloys and in refractories and ceramics