Etymology: Middle English, from Old English thæt, neut. demonstrative pronoun & definite article; akin to Old High German daz, neuter demonstrative pronoun & definite article, Greek to, Latin istud, neuter demonstrative pronoun
Date: before 12th century
1 a : the person, thing, or idea indicated, mentioned, or understood from the situation <that is my father> b : the time, action, or event specified <after that I went to bed> c : the kind or thing specified as follows <the purest water is that produced by distillation> d : one or a group of the indicated kind <that's a cat -- quick and agile>
2 a : the one farther away or less immediately under observation or discussion <those are maples and these are elms> b : the former one
3 a -- used as a function word after and to indicate emphatic repetition of the idea expressed by a previous word or phrase <he was helpful, and that to an unusual degree> b -- used as a function word immediately before or after a word group consisting of a verbal auxiliary or a form of the verb be preceded by there or a personal pronoun subject to indicate emphatic repetition of the idea expressed by a previous verb or predicate noun or predicate adjective <is she capable? She is that>
4 a : the one : the thing : the kind : SOMETHING, ANYTHING <the truth of that which is true> <the senses are that whereby we experience the world> <what's that you say> b plural : some persons <those who think the time has come>
- all that : everything of the kind indicated <tact, discretion, and all that>
- at that 1 : in spite of what has been said or implied 2 : in addition