DuckCorp Dico

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1.                 From The Collaborative International Dictionary of English v.0.48:
                   
   
   
                   
                     
   Slag \Slag\, v. i. & t. [imp. & p. p. Slagged; p. pr. & vb. n.
      Slagging.] (Metal.)
      To form, or form into, a slag; to agglomerate when heated
      below the fusion point.
      [Webster 1913 Suppl.]