The Collaborative International Dictionary of English v.0.48:

Polarization \Po`lar*i*za"tion\, n. [Cf. F. polarisation.]
   [1913 Webster]
   1. The act of polarizing; the state of being polarized, or of
      having polarity.
      [1913 Webster]

   2. (Opt.) A peculiar affection or condition of the rays of
      light or heat, in consequence of which they exhibit
      different properties in different directions.
      [1913 Webster]

   Note: If a beam of light, which has been reflected from a
         plate of unsilvered glass at an angle of about 56[deg],
         be received upon a second plate of glass similar to the
         former, and at the same angle of incidence, the light
         will be readily reflected when the two planes of
         incidence are parallel to each other, but will not be
         reflected when the two planes of incidence are
         perpendicular to each other. The light has, therefore,
         acquired new properties by reflection from the first
         plate of glass, and is called polarized light, while
         the modification which the light has experienced by
         this reflection is called polarization. The plane in
         which the beam of light is reflected from the first
         mirror is called the plane of polarization. The angle
         of polarization is the angle at which a beam of light
         must be reflected, in order that the polarization may
         be the most complete. The term polarization was derived
         from the theory of emission, and it was conceived that
         each luminous molecule has two poles analogous to the
         poles of a magnet; but this view is not now held.
         According to the undulatory theory, ordinary light is
         produced by vibrations transverse or perpendicular to
         the direction of the ray, and distributed as to show no
         distinction as to any particular direction. But when,
         by any means, these, vibrations are made to take place
         in one plane, the light is said to be plane polarized.
         If only a portion of the vibrations lie in one plane
         the ray is said to be partially polarized. Light may be
         polarized by several methods other than by reflection,
         as by refraction through most crystalline media, or by
         being transmitted obliquely through several plates of
         glass with parallel faces. If a beam of polarized light
         be transmitted through a crystal of quartz in the
         direction of its axis, the plane of polarization will
         be changed by an angle proportional to the thickness of
         the crystal. This phenomenon is called rotatory
         polarization. A beam of light reflected from a metallic
         surface, or from glass surfaces under certain peculiar
         conditions, acquires properties still more complex, its
         vibrations being no longer rectilinear, but circular,
         or elliptical. This phenomenon is called circular or
         elliptical polarization.
         [1913 Webster]

   3. (Elec.) An effect produced upon the plates of a voltaic
      battery, or the electrodes in an electrolytic cell, by the
      deposition upon them of the gases liberated by the action
      of the current. It is chiefly due to the hydrogen, and
      results in an increase of the resistance, and the setting
      up of an opposing electro-motive force, both of which tend
      materially to weaken the current of the battery, or that
      passing through the cell.
      [1913 Webster]

WordNet (r) 3.0 (2006):

polarization
    n 1: the phenomenon in which waves of light or other radiation
         are restricted in direction of vibration [syn:
         polarization, polarisation]
    2: the condition of having or giving polarity [syn:
       polarization, polarisation]

Moby Thesaurus II by Grady Ward, 1.0:

46 Moby Thesaurus words for "polarization":
   N pole, S pole, agreement to disagree, anteposition, antigravity,
   antithesis, centrifugal force, confrontation, confrontment,
   contention, contraposition, contrariety, contrast, cross-purposes,
   diamagnetism, difference, difference of opinion, difficulty,
   disaffinity, disagreement, disparity, dividedness, division,
   hostility, magnetic axis, magnetic pole, magnetic repulsion,
   misunderstanding, mutual repulsion, negative pole, north pole,
   odds, opposing, opposition, opposure, polar opposition, polarity,
   pole, posing against, positive pole, repellence, repellency,
   repelling, repulsion, south pole, variance