tense - What is 'deictic time'?

[5]
i  If she beats him he’ll claim she cheated. [non-deictic past]
ii If you eat any more you’ll say you don’t want any tea.[non-deictic present]

The preterite and present tense inflections on cheat and do indicate that T_r is respectively anterior to and simultaneous with T_o, but here T_o is clearly not T_d. The time of the (possible) cheating is not anterior to the time of my uttering [5i], but to the time of his (possibly) making a claim of cheating.
                   — The Cambridge Grammar of the English Language, p126

I can understand T_o (time of orientation = utterance time), yet don’t get what the ‘deictic time (T_d)’ is. Would you let me know the T_d?

Answer

Deictic (adjective form of deixis, 'pointing') is used in linguistics to designate expressions which explicitly refer to the spatial or temporal relationship between the speaker and what he is talking about. This and that are deictic adjectives or pronouns, and there, then, here, now, whence, whither, thither, hither are deictic adverbs, because they 'point' to objects or places or times from the standpoint of the speaker.

CGEL employs the term 'deictic time' (T_d) to designate the speaker's standpoint in time, the time from which he 'points' to the events he is talking about. Deictic time thus seems to be equivalent to what the Reichenbach model calls 'Speech Time' (abbreviated 'ST') or 'Utterance Time'. CGEL's T_r (time referred to) is Reichenbach's 'Event Time' ('ET'), and T_o (time of orientation) is Reichenbach's 'Reference Time' ('RT').

And when CGEL speaks of 'non-deictive past', it means that the past tense on cheated in he will claim she cheated is not past with reference to T_d—the speaker of the sentence is not 'pointing' to an event in the speaker's own past. The event lies in the past relative to T_o, the (future, hypothothetical) time when the claim of cheating is made.

There's a useful outline of the CGEL scheme here.