dislocation

In syntax, dislocation is a sentence structure in which a constituent which could otherwise be either an argument or an adjunct of the clause occurs outside the clause boundaries either to its left or to its right as in English They went to the store, Mary and Peter.

The dislocated element is often separated by a pause (comma in writing) from the rest of the sentence. Its place within the clause is often occupied by a pronoun (e.g. they).