any of various alloys of iron containing cobalt, nickel, aluminum, and occasionally copper, titanium, or niobium: used in making strong permanent magnets
See alnico in American Heritage Dictionary 4
(ălˈnĭ-kōˌ)
noun
Any of several hard, strong alloys of iron, aluminum, nickel, cobalt and sometimes copper, niobium, or tantalum, used to make strong permanent magnets.