The Collaborative International Dictionary of English v.0.48:

Weld \Weld\, v. t. [imp. & p. p. Welded; p. pr. & vb. n.
   Welding.] [Probably originally the same word as well to
   spring up, to gush; perhaps from the Scand.; cf. Sw.
   v[aum]lla to weld, uppv[aum]lla to boil up, to spring up,
   Dan. v[ae]lde to gush, G. wellen to weld. See Well to
   spring.]
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   1. To press or beat into intimate and permanent union, as two
      pieces of iron when heated almost to fusion.
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   Note: Very few of the metals, besides iron and platinum. are
         capable of being welded. Horn and tortoise shell
         possess this useful property.
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   2. Fig.: To unite closely or intimately.
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            Two women faster welded in one love.  --Tennyson.
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