In linguistics, deixis (/ˈdaɪksᵻs/) refers to words and phrases, such as “me” or “here”, that cannot be fully understood without additional contextual information -- in this case, the identity of the speaker (“me”) and the speaker's location (“here”). Words are deictic if their semantic meaning is fixed but their denotational meaning varies depending on time and/or place. Words or phrases that require contextual information to convey any meaning – for example, English pronouns – are deictic. Deixis is closely related to anaphora, as will be further explained below. Although this article deals primarily with deixis in spoken language, the concept is sometimes applied to written language, gestures, and communication media as well. In linguistic anthropology, deixis is treated as a particular subclass of the more general semiotic phenomenon of indexicality, a sign "pointing to" some aspect of its context of occurrence.
Although this article draws examples primarily from English, deixis is believed to be a feature (to some degree) of all natural languages. The term’s origin is Ancient Greek: deixis "display, demonstration, or reference", the meaning point of reference in contemporary linguistics having been taken over from Chrysippus.
Possibly the most common categories of contextual information referred to by deixis are those of person, place, and time - what Fillmore calls the “major grammaticalized types” of deixis.
Person deixis concerns itself with the grammatical persons involved in an utterance, (1) those directly involved (e.g. the speaker, the addressee), (2) those not directly involved (e.g. overhearers—those who hear the utterance but who are not being directly addressed), and (3) those mentioned in the utterance. In English, the distinctions are generally indicated by pronouns. The following examples show how. (The person deictic terms are in italics, a signaling notation that will continue through this article.)