Source : Webster's Revised Unabridged Dictionary (1913)

Cork \Cork\ (k[^o]rk), n. [Cf. G., Dan., & Sw. kork, D. kurk;
   all fr. Sp. corcho, fr. L. cortex, corticis, bark, rind. Cf.
   {Cortex}.]
   1. The outer layer of the bark of the cork tree ({Quercus
      Suber}), of which stoppers for bottles and casks are made.
      See {Cutose}.

   2. A stopper for a bottle or cask, cut out of cork.

   3. A mass of tabular cells formed in any kind of bark, in
      greater or less abundance.

   Note: Cork is sometimes used wrongly for calk, calker;
         calkin, a sharp piece of iron on the shoe of a horse or
         ox.

   {Cork jackets}, a jacket having thin pieces of cork inclosed
      within canvas, and used to aid in swimming.

   {Cork tree} (Bot.), the species of oak ({Quercus Suber} of
      Southern Europe) whose bark furnishes the cork of
      commerce.

Cork \Cork\ (k[^o]rk), n. [Cf. G., Dan., & Sw. kork, D. kurk;
   all fr. Sp. corcho, fr. L. cortex, corticis, bark, rind. Cf.
   {Cortex}.]
   1. The outer layer of the bark of the cork tree ({Quercus
      Suber}), of which stoppers for bottles and casks are made.
      See {Cutose}.

   2. A stopper for a bottle or cask, cut out of cork.

   3. A mass of tabular cells formed in any kind of bark, in
      greater or less abundance.

   Note: Cork is sometimes used wrongly for calk, calker;
         calkin, a sharp piece of iron on the shoe of a horse or
         ox.

   {Cork jackets}, a jacket having thin pieces of cork inclosed
      within canvas, and used to aid in swimming.

   {Cork tree} (Bot.), the species of oak ({Quercus Suber} of
      Southern Europe) whose bark furnishes the cork of
      commerce.

Source : WordNet®

Quercus suber
     n : medium-sized evergreen oak of southern Europe and northern
         Africa having thick corky bark that is periodically
         stripped to yield commercial cork [syn: {cork oak}]