In linguistics, anaphora is the use of an expression the interpretation of which depends upon another expression in context (its antecedent or postcedent). In a narrower sense, anaphora is the use of an expression which depends specifically upon an antecedent expression, and thus is contrasted with cataphora, which is the use of an expression which depends upon a postcedent expression. The anaphoric (referring) term is called an anaphor. For example, in the sentence Sally arrived, but nobody saw her, the pronoun her is an anaphor, referring back to the antecedent Sally. In the sentence Before her arrival, nobody saw Sally, the pronoun her refers forward to the postcedent Sally, so her is now a cataphor (and an anaphor in the broader, but not the narrower, sense). Usually, an anaphoric expression is a proform or some other kind of deictic (contextually-dependent) expression. Both anaphora and cataphora are species of endophora, referring to something mentioned elsewhere in a dialog or text.