The notion of reference can be conceived as a dyadic relation between an expression and an entity or a set of entities; these entities, which will be usually extralinguistic, are the referent of the expression. Nonetheless, it is relevant to make two qualifications. On the one hand, the term reference is very often used ambiguously, since it frequently occurs instead of the expression referent; however, the context will help avoid possible misunderstandings. On the other hand, reference can be understood not as a dyadic relation between a linguistic expression and its referent, but as a triadic relation between speakers, an expression and the referent. Nonetheless, we will not emphasize this distinction, since the assertions about the reference of expressions could be paraphrased as ones about the speakers’ use(s) of them in order to refer.