iron

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun A silvery-white, lustrous, malleable, ductile, magnetic or magnetizable, metallic element occurring abundantly in combined forms, notably in hematite, limonite, magnetite, and taconite, and used alloyed in a wide range of important structural materials. Atomic number 26; atomic weight 55.845; melting point 1,538°C; boiling point 2,861°C; specific gravity 7.874 (at 20°C); valence 2, 3, 4, 6. cross-reference: Periodic Table.
• noun An implement made of iron alloy or similar metal, especially a bar heated for use in branding, curling hair, or cauterizing.
• noun Great hardness or strength; firmness.
• noun Sports Any of a series of golf clubs having a bladelike metal head and numbered from one to nine in order of increasing loft.
• noun A metal appliance with a handle and a weighted flat bottom, used when heated to press wrinkles from fabric.
• noun A harpoon.
• noun Fetters; shackles.
• noun A tonic, pill, or other medication containing iron and taken as a dietary supplement.
• adjective Made of or containing iron.
• adjective Strong, healthy, and capable of great endurance.
• adjective Inflexible; unyielding.
• adjective Holding tightly; very firm.
• intransitive verb To press and smooth with a heated iron.
• intransitive verb To remove (creases) by pressing.
• intransitive verb To put into irons; fetter.
• intransitive verb To fit or clad with iron.
• intransitive verb To iron clothes.
• idiom (in irons) Lying head to the wind and unable to turn either way.
• idiom (iron in the fire) An undertaking or project in progress.

from The Century Dictionary.

• noun Chemical symbol, Fe; atomic weight, 56. A metal, the most abundant and the most important of all those used in the metallic form.
• noun A utensil or weapon made of iron: often in combination with a noun or an adjective expressive of its purpose or character : as, a flat-iron, gridiron, or shooting-iron (slang for pistol).
• noun Specifically— A knife, sword, or other cutting implement.
• noun plural Fetters or other chains fastened to the person of a prisoner: as, a mutineer is put in irons.
• noun In whaling, a hand-harpoon; a toggle-iron, used in striking a whale. There are two forms, the first and second irons (which see, below).
• noun A brand-iron.
• noun To have, as a square-rigged vessel, the yards so braced that, some sails being full of wind and some aback, the vessel is temporarily unmanageable.
• Made of iron; consisting of iron: as, an iron gate; an iron bar.
• Resembling iron in some respect, either really or metaphorically.
• Hence— Harsh; rude; severe.
• Binding fast ; not to be broken.
• Capable of great endurance; firm; robust: as, an iron constitution.
• Not to be bent; inflexible.
• In mining, same as gossan. [U.S.]
• To shackle with irons; fetter; handcuff.
• To furnish, mount, or arm with iron: as, to iron a wagon.
• To smooth with an instrument of iron, especially with a hot flat-iron, smoothing-iron, or box-iron.

from the GNU version of the Collaborative International Dictionary of English.

• adjective Of, or made of iron; consisting of iron.
• adjective Resembling iron in color.
• adjective Like iron in hardness, strength, impenetrability, power of endurance, insensibility, etc.
• adjective Rude; hard; harsh; severe.
• adjective Firm; robust; enduring.
• adjective Inflexible; unrelenting.
• adjective Not to be broken; holding or binding fast; tenacious.
• adjective (Myth.), (Archæol.) That stage in the development of any people characterized by the use of iron implements in the place of the more cumbrous stone and bronze.
• adjective a cement for joints, composed of cast-iron borings or filings, sal ammoniac, etc.
• adjective (Min.) a yellowish clay containing a large proportion of an ore of iron.
• adjective a German, and before that Prussian, order of military merit; also, the decoration of the order.