A referent /ˈrɛfərənt/ is a person or thing to which a linguistic expression or other symbol refers. For example, in the sentence Mary saw me, the referent of the word Mary is the particular person called Mary who is being spoken of, while the referent of the word me is the person uttering the sentence.
Two expressions which have the same referent are said to be co-referential. In the sentence John had his dog with him, for instance, the noun John and the pronoun him are co-referential, since they both refer to the same person (John).
The word may be considered to derive from the Latin referentem, the present participle (in accusative form) of the verb referre ("carry back", see also etymology of refer(ence)); or simply from the addition of the suffix -ent to the verb refer on the model of other English words having that suffix. It is defined in the Merriam-Webster Dictionary as "one that refers or is referred to; especially: the thing that a symbol (as a word or sign) stands for."
The earliest meaning of referent recorded in the Oxford English Dictionary is "one who is referred to or consulted", dating from 1844. A subsequent meaning is "a word referring to another"; the OED gives only one citation for this use, dating from 1899 (which speaks of "referent words or referents" that express a relation). The next meaning, which appears to stand in opposition to the previous meaning, as well as to the meaning implied by the etymology, is nonetheless the one which has gained currency: "that to which something [particularly a word or expression] has reference". This sense is first recorded in Ogden and Richards' The Meaning of Meaning (1923; see further below); the OED also lists numerous subsequent examples of that usage.