The Collaborative International Dictionary of English v.0.48:

Moon-eye \Moon"-eye`\, n.
   1. A eye affected by the moon; also, a disease in the eye of
      a horse.
      [1913 Webster]

   2. (Zool.)
      (a) Any species of American fresh-water fishes of the
          genus Hyodon, esp. Hyodon tergisus of the Great
          Lakes and adjacent waters.
      (b) The cisco.
          [1913 Webster]