Definition - The phenomenon of a word or phrase referring to something that has not been previously mentioned, thus the reader or listener uses situational knowledge to determine its significance.
1. As opposed to endophora where the key information has been previously mentioned.

Example -

(1) A women walks up to two men wearing a bikini. One of the men says to the other: "She was lying on the beach." Here the she is exophoric because the discourse hasn't given us any information as to who she is.
(2) In contrast, in the statement: "I saw David an hour ago. He was looking at his watch." the he is endophoric because it refers to something or someone (i.e., David) that was previously mentioned.

Etymology -
The word derives from the Greek exo, outside + pherein, to carry.

Oxford English Dictionary -
Its first citation is from 1976:
"We shall find it useful … to have a special term for situational reference. This we are referring to as *exophora, or exophoric reference."
(Halliday & Hasan Cohesion in Eng. ii. 33)

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