(noun)
a state of a group or society, characterized by interests, opinions, and beliefs that are concentrated on two opposite ends of a spectrum rather than ranging along the spectrum;
e.g. Polarization in a society increases the rates of conflict between people.
(noun)
in science (especially physics), the action of inducing a polarity onto something, especially magnetic polarity;
e.g. The polarization of a regular iron bar turns it into a magnet.
(noun)
in physics, the action of inducing a radiation, especially light, to have vibrations that only go in one direction;
e.g. The polarization of the light makes the experimental results easier to study.