Source : Webster's Revised Unabridged Dictionary (1913)

Surface \Sur"face`\, n. [F. See {Sur-}, and {Face}, and cf.
   {Superficial}.]
   1. The exterior part of anything that has length and breadth;
      one of the limits that bound a solid, esp. the upper face;
      superficies; the outside; as, the surface of the earth;
      the surface of a diamond; the surface of the body.

            The bright surface of this ethereous mold. --Milton.

   2. Hence, outward or external appearance.

            Vain and weak understandings, which penetrate no
            deeper than the surface.              --V. Knox.

   3. (Geom.) A magnitude that has length and breadth without
      thickness; superficies; as, a plane surface; a spherical
      surface.

   4. (Fort.) That part of the side which is terminated by the
      flank prolonged, and the angle of the nearest bastion.
      --Stocqueler.

   {Caustic surface}, {Heating surface}, etc. See under
      {Caustic}, {Heating}, etc.

   {Surface condensation}, {Surface condenser}. See under
      {Condensation}, and {Condenser}.

   {Surface gauge} (Mach.), an instrument consisting of a
      standard having a flat base and carrying an adjustable
      pointer, for gauging the evenness of a surface or its
      height, or for marking a line parallel with a surface.

   {Surface grub} (Zo["o]l.), the larva of the great yellow
      underwing moth ({Triph[oe]na pronuba}). It is often
      destructive to the roots of grasses and other plants.

   {Surface plate} (Mach.), a plate having an accurately dressed
      flat surface, used as a standard of flatness by which to
      test other surfaces.

   {Surface printing}, printing from a surface in relief, as
      from type, in distinction from plate printing, in which
      the ink is contained in engraved lines.



   3. (Chem.) An apparatus for receiving and condensing the
      volatile products of distillation to a liquid or solid
      form, by cooling.

   4. (Steam Engine) An apparatus, separate from the cylinder,
      in which the exhaust steam is condensed by the action of
      cold water or air. See Illust. of {Steam engine}.

   {Achromatic condenser} (Optics), an achromatic lens used as a
      condenser.

   {Bull's-eye condenser}, or {Bull's-eye} (Optics), a lens of
      short focal distance used for concentrating rays of light.
      

   {Injection condenser}, a vessel in which steam is condensed
      by the direct contact of water.

   {Surface condenser}, an apparatus for condensing steam,
      especially the exhaust of a steam engine, by bringing it
      into contact with metallic surface cooled by water or air.