The Collaborative International Dictionary of English v.0.48:

Hearth \Hearth\ (h[aum]rth), n. [OE. harthe, herth, herthe, AS.
   heor[eth]; akin to D. haard, heerd, Sw. h[aum]rd, G. herd;
   cf. Goth. ha['u]ri a coal, Icel. hyrr embers, and L. cremare
   to burn.]
   1. The pavement or floor of brick, stone, or metal in a
      chimney, on which a fire is made; the floor of a
      fireplace; also, a corresponding part of a stove.
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            There was a fire on the hearth burning before him.
                                                  --Jer. xxxvi.
                                                  22.
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            Where fires thou find'st unraked and hearths
            unswept.
            There pinch the maids as blue as bilberry. --Shak.
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   2. The house itself, as the abode of comfort to its inmates
      and of hospitality to strangers; fireside.
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            Household talk and phrases of the hearth.
                                                  --Tennyson.

   3. (Metal. & Manuf.) The floor of a furnace, on which the
      material to be heated lies, or the lowest part of a
      melting furnace, into which the melted material settles;
      as, an open-hearth smelting furnace.
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   Hearth ends (Metal.), fragments of lead ore ejected from
      the furnace by the blast.

   Hearth money, Hearth penny [AS. heor[eth]pening], a tax
      formerly laid in England on hearths, each hearth (in all
      houses paying the church and poor rates) being taxed at
      two shillings; -- called also chimney money, etc.
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            He had been importuned by the common people to
            relieve them from the . . . burden of the hearth
            money.                                --Macaulay.
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