n.1 a piece of iron, steel, alloy, ore, etc., usu. in the form of a bar or horseshoe, having properties of attracting or repelling iron.
2 a lodestone.
3 a person or thing that attracts.
Etymology: ME f. L magnes magnetis f. Gk magnes Magnes -etos (lithos) (stone) of Magnesia: cf. MAGNESIA