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.


from The American Heritage® Dictionary of the English Language, 4th Edition

[Middle English iren, from Old English īren; see eis- in Indo-European roots.]


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  • Can be spelled with the Periodic Table of Elements symbols: IrON

    December 12, 2006

  • A traditional unit of measure for the thickness of leather used in making shoes, especially soles. One iron is equal to 1/48 inch (0.5292 millimeter), so a sole that's 1/4-inch thick is described as "12 iron."

    November 6, 2007

  • Fe.

    December 16, 2007

  • There's a conversaton on this list about the pronunciation of this word. Since that long-ago time, I found out that "i-ern" is a quite common pronunciation in the United States, while "i-ron" is more common in the U.K. (don't know where else, perhaps Australia?).

    Just thought I'd mention it. Don't have the book with me so I can't cite it here just yet, but I will if anyone's interested.

    October 10, 2008

  • No iron tool of any kind was employed in the building of the Temple in order that quiet and reverence might prevail.

    (Source: Masonic dictionary)

    November 17, 2008

  • "iron" in Hungarian means: pencil (especially the one used by carpenters)

    August 7, 2012