Cinder (sĭnˈdẽr), 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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Slag (slăg), 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.
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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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