|1.||[ noun ] (geometry) the interchangeability of the roles of points and planes in the theorems of projective geometry|
|Related terms:||exchangeability geometry|
|2.||[ noun ] being twofold; a classification into two opposed parts or subclasses|
: "the dichotomy between eastern and western culture"
|Related terms:||classification dichotomize|
|3.||[ noun ] (physics) the property of matter and electromagnetic radiation that is characterized by the fact that some properties can be explained best by wave theory and others by particle theory|
|Related terms:||property physics|