In Noam Chomsky's government and binding theory in linguistics, an R-expression (short for "referring expression" (the linked article explains the different, broader usage in other theories of linguistics) or "referential expression") is a noun phrase that refers to a specific real or imaginary entity.
In contrast with anaphors and pronouns/pronominals, R-expressions obey condition C, which states that they are free, not bound to any other element.
R-expressions include determiner phrases that are definite, and names.
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