Meaning of ATOMIC NUMBER 40

WordNet Dictionary
	Definition:		[n]  a lustrous gray strong metallic element resembling titanium; it is used in nuclear reactors as a neutron absorber; it occurs in baddeleyite but is obtained chiefly from zircon
	Synonyms:		zirconium, Zr
	See Also:		baddeleyite, metal, metallic element, zircon, zirconium silicate