The Collaborative International Dictionary of English v.0.48:

Shower \Show"er\, v. t. [imp. & p. p. Showered; p. pr. & vb.
   n. Showering.]
   1. To water with a shower; to ??t copiously with rain.
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            Lest it again dissolve and shower the earth.
                                                  --Milton.
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   2. To bestow liberally; to destribute or scatter in ?undance;
      to rain. --Shak.
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            C?sar's favor,
            That showers down greatness on his friends.
                                                  --Addison.
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