Producing a more defined version of some OBJect by replacing variables with values (or other variables). 1. In OBJect-oriented programming, producing a particular OBJect from its class template. This involves allocation of a structure with the types specified by the template, and initialisation of instance variables with either default values or those provided by the class' s constructor function. 2. In unification, (as used in logic programming, {type checking} and {type inference}), binding a {logic variable} (type variable) to some value (type). (1995-03-28)