The Collaborative International Dictionary of English v.0.48:

Piper \Pip"er\, n.
   1. (Mus.) One who plays on a pipe, or the like, esp. on a
      bagpipe. "The hereditary piper and his sons." --Macaulay.
      [1913 Webster]

   2. (Zool.)
      (a) A common European gurnard (Trigla lyra), having a
          large head, with prominent nasal projection, and with
          large, sharp, opercular spines.
      (b) A sea urchin (Goniocidaris hystrix) having very long
          spines, native of both the American and European
          coasts.
          [1913 Webster]

   To pay the piper, to bear the cost, expense, or trouble.
      [1913 Webster]