A division into two parts, especially into two equal parts.
The act of bisecting.
Duality; the condition of being double.
The belief that the world is ruled by a pair of antagonistic forces, such as good and evil; the belief that man has two basic natures, the physical and the spiritual.
The view that the world consists of, or is explicable in terms of, two fundamental principles, such as mind and matter or good and evil.