(pronounced DIKE-sis) A deictic expression is one that has only one meaning but can refer to different entities within the same context. The referent of a deictic expression varies depending on the point of view of the speaker. Common examples of deictic expressions are I, you, here, tomorrow, and right and left.

When Jack and Jill are speaking and Jack says "I love you", the word "I" refers to Jack. When Jill utters the exact same sentence, however, the word "I" refers to Jill. The meaning of the deictic word "I" has not changed, only the entity to which it refers, since Jack and Jill have different points of reference.

One should be careful not to confuse deixis with ambiguity, which is when one expression has more than one meaning.
As tailchaser mentioned, deixis is a type of reference where the referent can only be understood in the context of the utterance because it relies on inherently relative terms. "The referent is located using the current speech event or one of the participants as reference points" and so in some ways, you really had to have been there; otherwise you simply wouldn't be able make the reference.1

Some typical examples of deixis are:

I don't like it here.
Yeah, Mary was really happy then.
You can return the book over there.
In each of these cases, the referent of the deictic word would change depending upon where, when, and by whom it was uttered. If the first sentence were uttered by myself in Paris, then 'I' and 'here' would refer to myself and Paris, respectively. It would be different if Charlie Brown uttered it in the Great Pumpkin Patch. Contrast these sentences with:
Charlie Brown doesn't like it in the Great Pumpkin Patch.
Yeah, Mary was really happy on her 21st birthday.
Students can return books in the outside slot.
No matter who says these sentences (and when) the meaning stays the same (assuming we can all agree on who Mary, etc. are).

Note that deixis is different from ambiguity or non-specificity:

It's too bad that John couldn't come. He should have told us before.
In this case, the use of "before" (or alternatively, "ahead of time"), even though it is not specific and is relative, it is relative to some event, and not to the time of the utterance. It could have been uttered the day before or the day after, or even by other speakers and the meaning of before would have been exactly the same.

Spatial Deixis

Mostly manifests itself in here/there and this/that. While English currently has only two ways to reference space, (proximal/distal), this wasn't always the case and certainly isn't true for all languages. Most languages that have three categories sub-divide the distal category into distal and remote, as can be seen in older English as here/there/yonder. Another way that languages can divide up space is into "near to me", "near to you", and "not near to either you or me".

Here means generally close to the speaker, and there means generally distant from the speaker. It's important to note that the extent of these terms is usally determined by context. A speaker could say "I really like it here" one day and mean the city, and then go home and say "It's a pig-sty in here" and mean only the kitchen. In fact, there is no limit on how far 'here' can extend -- one could even say "Here in our solar system..." or even "Here in our galaxy..."

Psychologically, spatial deixis seems to be our prototypical way to view things relative to us, and corollaries can be seen in the other forms. Our feelings of near and far are very innate to us and we tend to use them to "bring closer" or "distance" concepts from ourselves depending on our emotions. This is typically done with this and that.

That worker should be shot. -- makes him remote
This paper is genius. -- brings it closer; we identify with it more
Person Deixis

Person deixis is strongly influenced by the dominance that the speaker (first person) exerts over the discourse. The speaker is the deictic center, the listener is anchored to that center (second person), and all other entities are outside of that deictic center (third person). Without going into boring detail, people mentioned who are closer in the circle dominate the use of pronouns over those who are further away.

Examples: I, you, he/she, it, we, you, they. We could either be inclusive if it includes the listener or exclusive if it does not.

Temporal Deixis

Primary terms are now and then. Now is very much a temporal version of here, generally referring to the time of the utterance, though its scope can be just as extended as here's. "The tectonic plates are going through a period of relative calm now."

Then points away from the present, either to the future or to the past. Other deictic terms are yesterday, today, tomorrow, next (month) and last (month).2

Social Deixis

Expresses the intimate/not-intimate distinction exemplified by the tu/vous pronouns in French. Some examples are in Japanese: honorifics, in English: Sir/Madame, and in French: Monsieur/Madame.

Discourse Deixis

Used to refer to discourse elements themselves, either occuring in the future of the past.

This joke will kill you.
That story wasn't very interesting.
1+1=2. The truth of this statement is guaranteed by mathematical logic.
The reason these are considered deictic items is because in each case, the meaning of the term is relative to what just was just said or what is about to come. This is different from anaphora where a repeated reference refers to the same entity:
Sally left the house in a hurry. She seemed upset.
When 'she' refers back to the same entity as the word 'Sally' (the woman), it doesn't actually refer back to the lexical item Sally. This is different from referring to an upcoming lexical utterance, like a joke in the case above.

Gesture Deixis

This kind of deixis requires a gesture or motion of some sort to identify the item that is being referred to in the utterance.

I'd like that coat.
Will you please sign here?
Ok, I want you, you, and you.

Information from:
Cruse, Alan, Meaning in Language: An Introduction to Semantics and Pragmatics, Oxford University Press, Oxford, 2000.
1 Ibid, p. 319.
2 The use of this as in "this week" or "this July", while being used in a temporal context, is actually an extended form of the spatial this (or so he says).

Log in or register to write something here or to contact authors.