Duality is a concept that refers to TWO distinct parts or aspects of something. It can be seen in many different contexts, such as in philosophy, religion, and mathematics. The term duality can be broken down into three parts: TWO (3 letters), PAIR (4 letters), and dualism (7 letters). TWO refers to the TWO distinct parts or aspects, PAIR refers to the relationship between the TWO parts, and dualism refers to the idea that the TWO parts are separate yet interconnected.