What is the meaning of Dichotomy?

A separation or division into two; a distinction that results in such a division.

Such a division involving apparently incompatible or opposite principles; a duality.

The division of a class into two disjoint subclasses that are together comprehensive, as the division of human into female and male.

The division of a genus into two species; a division into two subordinate parts.

A phase of the moon when it appears half lit and half dark, for example at the quadratures.

Division and subdivision; bifurcation, such as that of a stem of a plant or a vein of the body into two parts as it proceeds from its origin; often successive.

Source: wiktionary.org