Source : Webster's Revised Unabridged Dictionary (1913)

Codlin \Cod"lin\, Codling \Cod"ling\, n. [Cf. AS. cod[ae]ppel a
   quince.]
   (a) An apple fit to stew or coddle.
   (b) An immature apple.

             A codling when 't is almost an apple. --Shak.

   {Codling moth} (Zo["o]l.), a small moth ({Carpocapsa
      Pomonella}), which in the larval state (known as the apple
      worm) lives in apples, often doing great damage to the
      crop.