Source : Webster's Revised Unabridged Dictionary (1913)

Cod liver \Cod" liv`er\, n.
   The liver of the common cod and allied species.

   {Cod-liver oil}, an oil obtained from the liver of the
      codfish, and used extensively in medicine as a means of
      supplying the body with fat in cases of malnutrition.

Source : WordNet®

cod-liver oil
     n : an oil obtained from the livers of cod and similar fishes;
         taken orally as a source of vitamins A and D [syn: {cod
         liver oil}]