Gall \Gall\ (g[add]l), n. [F. galle, noix de galle, fr. L.

           galla.] (Zool.)
   An excrescence of any form produced on
         any part of a plant by
   insects or their larvae. They are
         most commonly caused by
   small Hymenoptera and Diptera
         which puncture the bark and lay
   their eggs in the
         wounds. The larvae live within the galls.
   Some galls are
         due to aphids, mites, etc. See Gallnut.
   [1913
         Webster]

   Note: The galls, or gallnuts, of commerce are
         produced by
         insects of the genus Cynips, chiefly on an oak
         (Quercus
         infectoria syn. Quercus Lusitanica) of
         Western Asia and Southern Europe. They contain much
         tannin, and are used in the manufacture of that article
         and for making ink and a black dye, as well as in
         medicine.
         [1913 Webster]

   Gall insect (Zool.), any insect that
         produces galls.

   Gall midge (Zool.), any small
         dipterous insect that
      produces galls.

   {Gall
         oak}, the oak (Quercus infectoria) which yields the
     
         galls of commerce.

   Gall of glass, the neutral salt
         skimmed off from the
      surface of melted crown glass;-
         called also glass
         gall
      and sandiver. --Ure.

  
         Gall wasp. (Zool.) See
         Gallfly.
      [1913
         Webster]