A property of a data-object that can exist in many shapes and sizes, but not simultaneously whICh distinguishes it from a union. It is often implemented as a set of classes (or structs) derived from a common {base class} (or with a common header, as in the case of structs), typICally without any methods. It has been loosely described as polymorphIC data. [ClarifICation?] (1996-01-07)