Equative

The term equative is used in linguistics to refer to constructions where two entities are equated with each other. For example, the sentence Susan is our president, equates two entities "Susan" and "our president". In English, equatives are typically expressed using a copular verb such as "be", although this is not the only use of this verb. Equatives can be contrasted with predicative constructions where one entity is identified as a member of a set, such as Susan is a president.
Different world languages approach equatives in different ways. The major difference between languages is whether or not they use a copular verb or a non-verbal element (e.g.demonstrative pronoun) to equate the two expressions.
The term equative is also sometimes applied to comparative-like constructions in which the degrees compared are identical rather than distinct: e.g., John is as stupid as he is fat.