deictic

1. Logic. Directly proving by argument.
2. Linguistics. Of or relating to a word, the determination of whose referent is dependent on the context in which it is said or written. In the sentence I want him to come here now, the words I, here, him, and now are deictic because the determination of their referents depends on who says that sentence, and where, when, and of whom it is said.

[Greek deiktikos, from deiktos, able to show directly, from deiknunai, to show.]

Adjective from deixis (See indexical).

The noun has one meaning:

Meaning #1: a word specifying identity or spacial or temporal location from the perspective of a speaker or hearer in the context in which the communication occurs
  Synonym: deictic word

The adjective deictic has one meaning:

Meaning #1: relating to or characteristic of a word whose reference depends on the circumstances of its use
  Pertains to noun: deixis (meaning #1)