That  —demons. Pron. (pl. Those) 1 person or thing indicated, named, or understood (i heard that; who is that in the garden?). 2 contrasted with this (this is much better than that). 3 (esp. In relative constructions) the one, the person, etc. (a table like that described above). 4  (pl. That) used instead of which or whom to introduce a defining clause (the book that you sent me; there is nothing here that matters). —demons. Adj. (pl. Those) designating the person or thing indicated, named, understood, etc. (cf. Sense 1 of pron.). —adv. 1 to such a degree; so (have done that much). 2 colloq. Very (not that good). —conj. Introducing a subordinate clause indicating: 1 statement or hypothesis (they say that he is better). 2 purpose (we eat that we may live). 3 result (am so sleepy that i cannot work).  all that very (not all that good). That is (or that is to say) formula introducing or following an explanation of a preceding word or words. That's that formula indicating conclusion or completion. [old english]