cobalt
co•balt (kō´bôlt´) n.
[[Ger kobalt: so named (c. 1730) by Georg Brandt (1694-1768), Swed chemist < Ger kobold, lit., goblin; term used for the ore by miners, who regarded it as worthless and as injurious because of its arsenic content]]
a hard, lustrous, steel-gray, ductile, metallic chemical element, found in various ores: it is used in the preparation of magnetic, wear-resistant, and high-strength alloys: its compounds are used in the production of inks, paints, and varnishes: symbol, Co; at. no. 27: a radioactive isotope (cobalt-60) is used in the treatment of cancer, in research, etc.: see the periodic table of elements in the Reference Supplement