DuckCorp Dico

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1.                 From The Collaborative International Dictionary of English v.0.48:
                   
   
   
                   
                     
   Pur \Pur\, v. i. [imp. & p. p. Purred; p. pr. & vb. n.
      Purring.] [Of imitative origin; cf. Prov. G. purren.]
      To utter a low, murmuring, continued sound, as a cat does
      when pleased. [Written also purr.]
      [1913 Webster]