Source : Webster's Revised Unabridged Dictionary (1913)

Auricle \Au"ri*cle\, n. [L. auricula, dim. of auris ear. See
   {Ear}.]
   1. (Anat.)
      (a) The external ear, or that part of the ear which is
          prominent from the head.
      (b) The chamber, or one of the two chambers, of the heart,
          by which the blood is received and transmitted to the
          ventricle or ventricles; -- so called from its
          resemblance to the auricle or external ear of some
          quadrupeds. See {Heart}.

   2. (Zo["o]l.) An angular or ear-shaped lobe.

   3. An instrument applied to the ears to give aid in hearing;
      a kind of ear trumpet. --Mansfield.

Source : WordNet®

auricle
     n 1: a small conical pouch projecting from the upper anterior
          part of each atrium of the heart [syn: {atrial auricle},
           {auricula atrii}]
     2: the externally visible cartilaginous structure of the
        external ear [syn: {pinna}, {ear}]