the most common and most useful metallic element, being of almost universal occurrence, usually in the form of an oxide (as hematite, magnetite, etc.), or a hydrous oxide (as limonite, turgite, etc.). it is reduced on an enormous scale in three principal forms; viz., cast iron, steel, and wrought iron. iron usually appears dark brown, from oxidation or impurity, but when pure, or on a fresh surface, is a gray or white metal. it is easily oxidized (rusted) by moisture, and is attacked by many corrosive agents. symbol fe (latin ferrum). atomic weight 55.9. specific gravity, pure iron, 7.86; cast iron, 7.1. in magnetic properties, it is superior to all other substances.-an instrument or utensil made of iron; -- chiefly in composition; as, a flatiron, a smoothing iron, etc.-fetters; chains; handcuffs; manacles.-strength; power; firmness; inflexibility; as, to rule with a rod of iron.-of, or made of iron; consisting of iron; as, an iron bar, dust.-resembling iron in color; as, iron blackness.-like iron in hardness, strength, impenetrability, power of endurance, insensibility, etc.;-rude; hard; harsh; severe.-firm; robust; enduring; as, an iron constitution.-inflexible; unrelenting; as, an iron will.-not to be broken; holding or binding fast; tenacious.-to smooth with an instrument of iron; especially, to smooth, as cloth, with a heated flatiron; -- sometimes used with out.-to shackle with irons; to fetter or handcuff.-to furnish or arm with iron; as, to iron a wagon.