Exemplification, in the philosophy of language, is a mode of symbolization characterized by the relation between a sample and what it refers to.
Unlike ostension, which is the act of showing or pointing to a sample, exemplification is possession of a property plus reference to its label (Goodman, 1976).
At its most basic, possession of a property amounts to being correctly referred to by its label.
In other words, an entity, 'x' can be said to possess a certain property if and only if: (1) there can be an abstract singular term which denotes that property, and (2) those assertions are true which predicate such an abstract term of a name or phrase denoting x.
The sample exemplifies green, it stands for it, and in this way exemplification is a mode of reference.