Source : Webster's Revised Unabridged Dictionary (1913)

Iron \I"ron\ ([imac]"[u^]rn), n. [OE. iren, AS. [=i]ren,
   [=i]sen, [=i]sern; akin to D. ijzer, OS. [=i]sarn, OHG.
   [=i]sarn, [=i]san, G. eisen, Icel. [=i]sarn, j[=a]rn, Sw. &
   Dan. jern, and perh. to E. ice; cf. Ir. iarann, W. haiarn,
   Armor. houarn.]
   1. (Chem.) 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.

   Note: The value of iron is largely due to the facility with
         which it can be worked. Thus, when heated it is
         malleable and ductile, and can be easily welded and
         forged at a high temperature. As cast iron, it is
         easily fusible; as steel, is very tough, and (when
         tempered) very hard and elastic. Chemically, iron is
         grouped with cobalt and nickel. Steel is a variety of
         iron containing more carbon than wrought iron, but less
         that cast iron. It is made either from wrought iron, by
         roasting in a packing of carbon (cementation) or from
         cast iron, by burning off the impurities in a Bessemer
         converter (then called Bessemer steel), or directly
         from the iron ore (as in the Siemens rotatory and
         generating furnace).

   2. An instrument or utensil made of iron; -- chiefly in
      composition; as, a flatiron, a smoothing iron, etc.

            My young soldier, put up your iron.   --Shak.

   3. pl. Fetters; chains; handcuffs; manacles.

            Four of the sufferers were left to rot in irons.
                                                  --Macaulay.

   4. Strength; power; firmness; inflexibility; as, to rule with
      a rod of iron.

   {Bar iron}. See {Wrought iron} (below).

   {Bog iron}, bog ore; limonite. See {Bog ore}, under {Bog}.

   {Cast iron} (Metal.), an impure variety of iron, containing
      from three to six percent of carbon, part of which is
      united with a part of the iron, as a carbide, and the rest
      is uncombined, as graphite. It there is little free
      carbon, the product is white iron; if much of the carbon
      has separated as graphite, it is called gray iron. See
      also {Cast iron}, in the Vocabulary.

   {Fire irons}. See under {Fire}, n.

   {Gray irons}. See under {Fire}, n.

   {Gray iron}. See {Cast iron} (above).

   {It irons} (Naut.), said of a sailing vessel, when, in
      tacking, she comes up head to the wind and will not fill
      away on either tack.

   {Magnetic iron}. See {Magnetite}.

   {Malleable iron} (Metal.), iron sufficiently pure or soft to
      be capable of extension under the hammer; also, specif., a
      kind of iron produced by removing a portion of the carbon
      or other impurities from cast iron, rendering it less
      brittle, and to some extent malleable.

   {Meteoric iron} (Chem.), iron forming a large, and often the
      chief, ingredient of meteorites. It invariably contains a
      small amount of nickel and cobalt. Cf. {Meteorite}.

   {Pig iron}, the form in which cast iron is made at the blast
      furnace, being run into molds, called pigs.

   {Reduced iron}. See under {Reduced}.

   {Specular iron}. See {Hematite}.

   {Too many irons in the fire}, too many objects requiring the
      attention at once.

   {White iron}. See {Cast iron} (above).

   {Wrought iron} (Metal.), the purest form of iron commonly
      known in the arts, containing only about half of one per
      cent of carbon. It is made either directly from the ore,
      as in the Catalan forge or bloomery, or by purifying
      (puddling) cast iron in a reverberatory furnace or
      refinery. It is tough, malleable, and ductile. When formed
      into bars, it is called bar iron.

Iron \I"ron\ ([imac]"[u^]rn), a. [AS. [=i]ren, [=i]sen. See
   {Iron}, n.]
   1. Of, or made of iron; consisting of iron; as, an iron bar,
      dust.

   2. Resembling iron in color; as, iron blackness.

   3. Like iron in hardness, strength, impenetrability, power of
      endurance, insensibility, etc.; as:
      (a) Rude; hard; harsh; severe.

                Iron years of wars and dangers.   --Rowe.

                Jove crushed the nations with an iron rod.
                                                  --Pope.
      (b) Firm; robust; enduring; as, an iron constitution.
      (c) Inflexible; unrelenting; as, an iron will.
      (d) Not to be broken; holding or binding fast; tenacious.
          ``Him death's iron sleep oppressed.'' --Philips.

   Note: Iron is often used in composition, denoting made of
         iron, relating to iron, of or with iron; producing
         iron, etc.; resembling iron, literally or figuratively,
         in some of its properties or characteristics; as,
         iron-shod, iron-sheathed, iron-fisted, iron-framed,
         iron-handed, iron-hearted, iron foundry or
         iron-foundry.

   {Iron age}.
      (a) (Myth.) The age following the golden, silver, and
          bronze ages, and characterized by a general
          degeneration of talent and virtue, and of literary
          excellence. In Roman literature the Iron Age is
          commonly regarded as beginning after the taking of
          Rome by the Goths, A. D. 410.
      (b) (Arch[ae]ol.) 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.

   {Iron cement}, a cement for joints, composed of cast-iron
      borings or filings, sal ammoniac, etc.

   {Iron clay} (Min.), a yellowish clay containing a large
      proportion of an ore of iron.

   {Iron cross}, a Prussian order of military merit; also, the
      decoration of the order.

   {Iron crown}, a golden crown set with jewels, belonging
      originally to the Lombard kings, and indicating the
      dominion of Italy. It was so called from containing a
      circle said to have been forged from one of the nails in
      the cross of Christ.

   {Iron flint} (Min.), an opaque, flintlike, ferruginous
      variety of quartz.

   {Iron founder}, a maker of iron castings.

   {Iron foundry}, the place where iron castings are made.

   {Iron furnace}, a furnace for reducing iron from the ore, or
      for melting iron for castings, etc.; a forge; a
      reverberatory; a bloomery.

   {Iron glance} (Min.), hematite.

   {Iron hat}, a headpiece of iron or steel, shaped like a hat
      with a broad brim, and used as armor during the Middle
      Ages.

   {Iron horse}, a locomotive engine. [Colloq.]

   {Iron liquor}, a solution of an iron salt, used as a mordant
      by dyers.

   {Iron man} (Cotton Manuf.), a name for the self-acting
      spinning mule.

   {Iron} {mold or mould}, a yellow spot on cloth stained by
      rusty iron.

   {Iron ore} (Min.), any native compound of iron from which the
      metal may be profitably extracted. The principal ores are
      magnetite, hematite, siderite, limonite, G["o]thite,
      turgite, and the bog and clay iron ores.

   {Iron pyrites} (Min.), common pyrites, or pyrite. See
      {Pyrites}.

   {Iron sand}, an iron ore in grains, usually the magnetic iron
      ore, formerly used to sand paper after writing.

   {Iron scale}, the thin film which on the surface of wrought
      iron in the process of forging. It consists essentially of
      the magnetic oxide of iron, {Fe3O4>}.

   {Iron works}, a furnace where iron is smelted, or a forge,
      rolling mill, or foundry, where it is made into heavy
      work, such as shafting, rails, cannon, merchant bar, etc.

Iron \I"ron\ ([imac]"[u^]rn), a. [AS. [=i]ren, [=i]sen. See
   {Iron}, n.]
   1. Of, or made of iron; consisting of iron; as, an iron bar,
      dust.

   2. Resembling iron in color; as, iron blackness.

   3. Like iron in hardness, strength, impenetrability, power of
      endurance, insensibility, etc.; as:
      (a) Rude; hard; harsh; severe.

                Iron years of wars and dangers.   --Rowe.

                Jove crushed the nations with an iron rod.
                                                  --Pope.
      (b) Firm; robust; enduring; as, an iron constitution.
      (c) Inflexible; unrelenting; as, an iron will.
      (d) Not to be broken; holding or binding fast; tenacious.
          ``Him death's iron sleep oppressed.'' --Philips.

   Note: Iron is often used in composition, denoting made of
         iron, relating to iron, of or with iron; producing
         iron, etc.; resembling iron, literally or figuratively,
         in some of its properties or characteristics; as,
         iron-shod, iron-sheathed, iron-fisted, iron-framed,
         iron-handed, iron-hearted, iron foundry or
         iron-foundry.

   {Iron age}.
      (a) (Myth.) The age following the golden, silver, and
          bronze ages, and characterized by a general
          degeneration of talent and virtue, and of literary
          excellence. In Roman literature the Iron Age is
          commonly regarded as beginning after the taking of
          Rome by the Goths, A. D. 410.
      (b) (Arch[ae]ol.) 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.

   {Iron cement}, a cement for joints, composed of cast-iron
      borings or filings, sal ammoniac, etc.

   {Iron clay} (Min.), a yellowish clay containing a large
      proportion of an ore of iron.

   {Iron cross}, a Prussian order of military merit; also, the
      decoration of the order.

   {Iron crown}, a golden crown set with jewels, belonging
      originally to the Lombard kings, and indicating the
      dominion of Italy. It was so called from containing a
      circle said to have been forged from one of the nails in
      the cross of Christ.

   {Iron flint} (Min.), an opaque, flintlike, ferruginous
      variety of quartz.

   {Iron founder}, a maker of iron castings.

   {Iron foundry}, the place where iron castings are made.

   {Iron furnace}, a furnace for reducing iron from the ore, or
      for melting iron for castings, etc.; a forge; a
      reverberatory; a bloomery.

   {Iron glance} (Min.), hematite.

   {Iron hat}, a headpiece of iron or steel, shaped like a hat
      with a broad brim, and used as armor during the Middle
      Ages.

   {Iron horse}, a locomotive engine. [Colloq.]

   {Iron liquor}, a solution of an iron salt, used as a mordant
      by dyers.

   {Iron man} (Cotton Manuf.), a name for the self-acting
      spinning mule.

   {Iron} {mold or mould}, a yellow spot on cloth stained by
      rusty iron.

   {Iron ore} (Min.), any native compound of iron from which the
      metal may be profitably extracted. The principal ores are
      magnetite, hematite, siderite, limonite, G["o]thite,
      turgite, and the bog and clay iron ores.

   {Iron pyrites} (Min.), common pyrites, or pyrite. See
      {Pyrites}.

   {Iron sand}, an iron ore in grains, usually the magnetic iron
      ore, formerly used to sand paper after writing.

   {Iron scale}, the thin film which on the surface of wrought
      iron in the process of forging. It consists essentially of
      the magnetic oxide of iron, {Fe3O4>}.

   {Iron works}, a furnace where iron is smelted, or a forge,
      rolling mill, or foundry, where it is made into heavy
      work, such as shafting, rails, cannon, merchant bar, etc.

Iron \I"ron\, v. t. [imp. & p. p. {Ironed}; p. pr. & vb. n.
   {Ironing}.]
   1. To smooth with an instrument of iron; especially, to
      smooth, as cloth, with a heated flatiron; -- sometimes
      used with out.

   2. To shackle with irons; to fetter or handcuff. ``Ironed
      like a malefactor.'' --Sir W. Scott.

   3. To furnish or arm with iron; as, to iron a wagon.

Iron \I"ron\ ([imac]"[u^]rn), n. (Golf)
   An iron-headed club with a deep face, chiefly used in making
   approaches, lifting a ball over hazards, etc.

Source : WordNet®

iron
     adj : extremely robust; "an iron constitution" [syn: {cast-iron}]

iron
     v : press and smooth with a heated iron; "press your shirts"
         [syn: {iron out}]

iron
     n 1: a heavy ductile magnetic metallic element; is silver-white
          in pure form but readily rusts; used in construction and
          tools and armament; plays a role in the transport of
          oxygen by the blood [syn: {Fe}, {atomic number 26}]
     2: a golf club that has a relatively narrow metal head
     3: metal shackles; for hands or legs [syn: {irons}, {chain}, {chains}]
     4: implement used to brand live stock [syn: {branding iron}]
     5: home appliance consisting of a flat metal base that is
        heated and used to smooth cloth [syn: {smoothing iron}]

Source : Free On-Line Dictionary of Computing

iron
     
        Hardware, especially older and larger hardware of {mainframe}
        class with big metal cabinets housing relatively low-density
        electronics (but the term is also used of modern
        {supercomputer}s).  Often in the phrase {big iron}.  Oppose
        {silicon}.
     
        See also {dinosaur}.
     
        [{Jargon File}]
     
        (1994-11-04)