THAT

pron., adj., adv., & conj.
—demons.pron. (pl. those)
1 the person or thing indicated, named, or understood, esp. when observed by the speaker or when familiar to the person addressed (I heard that; who is that in the garden?; I knew all that before; that is not fair).
2 (contrasted with this) the further or less immediate or obvious etc. of two (this bag is much heavier than that).
3 the action, behaviour, or circumstances just observed or mentioned (don't do that again).
4 Brit. (on the telephone etc.) the person spoken to (who is that?).
5 colloq. referring to a strong feeling just mentioned ('Are you glad?' 'I am that').
6 (esp. in relative constructions) the one, the person, etc., described or specified in some way (those who have cars can take the luggage; those unfit for use; a table like that described above).
7 (pl. that) used instead of which or whom to introduce a defining clause, esp. one essential to identification (the book that you sent me; there is nothing here that matters).
Usage:
As a relative that usually specifies, whereas who or which need not: compare the book that you sent me is lost with the book, which I gave you, is lost.
—demons.adj. (pl. those)
1 designating the person or thing indicated, named, understood, etc. (cf.
sense
1 of pron.) (look at that dog; what was that noise?; things were easier in those days).
2 contrasted with this (cf. sense 2 of pron.) (this bag is heavier than that one).
3 expressing strong feeling (shall not easily forget that day).
—adv.
1 to such a degree; so (have done that much; will go that far).
2 Brit. colloq. very (not that good).
3 at which, on which, etc. (at the speed that he was going he could not stop; the day that I first met her).
Usage:
Often omitted in this sense: the day I first met her.
—conj. introducing a subordinate clause indicating:
1 a statement or hypothesis (they say that he is better; there is no doubt that he meant it; the result was that the handle fell off).
2 a purpose (we live that we may eat).
3 a result (am so sleepy that I cannot keep my eyes open).
4 a reason or clause (it is rather that he lacks the time).
5 a wish (Oh, that summer were here!).
Usage:
Often omitted in senses 1, 3: they say he is better.
Phrases and idioms:
all that very (not all that good). and all that (or and that colloq.) and all or various things associated with or similar to what has been mentioned; and so forth. like that
1 of that kind (is fond of books like that).
2 in that manner, as you are doing, as he has been doing, etc. (wish they would not talk like that).
3 colloq. without effort (did the job like that).
4 of that character (he would not accept any payment — he is like that). that is (or that is to say) a formula introducing or following an explanation of a preceding word or words. that's colloq. you are (by virtue of present or future obedience etc.) (that's a good boy). that's more like it an acknowledgement of improvement. that's right an expression of approval or colloq. assent. that's that a formula concluding a narrative or discussion or indicating completion of a task. that there sl.
= sense
1 of adj. that will do no more is needed or desirable.
Etymology: OE thaeligt, nom. & acc. sing. neut. of demons. pron. & adj. se, seo, thaeligt f. Gmc; those f. OE thas pl. of thes THIS