The Collaborative International Dictionary of English v.0.48:

Patter \Pat"ter\, v. i. [imp. & p. p. Pattered; p. pr. & vb.
   n. Pattering.] [Freq. of pat to strike gently.]
   1. To strike with a quick succession of slight, sharp sounds;
      as, pattering rain or hail; pattering feet.
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            The stealing shower is scarce to patter heard.
                                                  --Thomson.
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   2. To mutter; to mumble; as, to patter with the lips.
      --Tyndale. [In this sense, and in the following, perh.
      from paternoster.]
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   3. To talk glibly; to chatter; to harangue. [Colloq.]
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            I've gone out and pattered to get money. --Mayhew.
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