cinder
    n 1: a fragment of incombustible matter left after a wood or
         coal or charcoal fire [syn: cinder, clinker]

Slag \Slag\ (sl[a^]g), n. [Sw. slagg, or LG. slacke, whence G.
   schlacke; originally, perhaps, the splinters struck off from
   the metal by hammering. See Slay, v. t.]
   1. The dross, or recrement, of a metal; also, vitrified
      cinders.
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   2. The scoria of a volcano.
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   3. (Metal.) A product of smelting, containing, mostly as
      silicates, the substances not sought to be produced as
      matte or metal, and having a lower specific gravity than
      the latter; -- called also, esp. in iron smelting,
      cinder. The slag of iron blast furnaces is essentially
      silicate of calcium, magnesium, and aluminium; that of
      lead and copper smelting furnaces contains iron.
      [Webster 1913 Suppl.]

   Slag furnace, or Slag hearth (Metal.), a furnace, or
      hearth, for extracting lead from slags or poor ore.

   Slag wool, mineral wool. See under Mineral.
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Cinder \Cin"der\ (s[i^]n"d[~e]r), n. [AS. sinder slag, dross;
   akin to Icel. sindr dross, Sw. sinder, G. sinter, D. sintel;
   perh. influenced by F. cendre ashes, fr. L. cinis. Cf.
   Sinter.]
   1. Partly burned or vitrified coal, or other combustible, in
      which fire is extinct.
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   2. A hot coal without flame; an ember. --Swift.
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   3. A scale thrown off in forging metal.
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   4. The slag of a furnace, or scoriaceous lava from a volcano.
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   Cinder frame, a framework of wire in front of the tubes of
      a locomotive, to arrest the escape of cinders.

   Cinder notch (Metal.), the opening in a blast furnace,
      through which melted cinder flows out.
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