Powerful \Pow"er*ful\, a.
   1. Full of power; capable of producing great effects of any
      kind; potent; mighty; efficacious; intense; as, a powerful
      man or beast; a powerful engine; a powerful argument; a
      powerful light; a powerful vessel.
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            The powerful grace that lies
            In herbs, plants, stones, and their true qualities.
                                                  --Shak.
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   2. (Mining) Large; capacious; -- said of veins of ore.
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   Syn: Mighty; strong; potent; forcible; efficacious;
        energetic; intense.
        [1913 Webster] -- Pow"er*ful*ly, adv. --
        Pow"er*ful*ness, n.
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