all that Definition

that
adj those (plural)

1. Indicating the thing, person or idea already mentioned, specified or understood.

Example: There's that girl I was telling you about
2. Indicating someone or something that is farther away or is in contrast.

Example: not this book, but that one

pronoun those (plural)

1. The person, thing or idea just mentioned, already spoken of or understood

Example: When did that happen?
2. A relatively distant or more distant person, thing or idea.

pronoun

1. Used instead of which, who or whom, to introduce a relative clause which defines, distinguishes or restricts the person or thing mentioned in the preceding clause.

Example: All the children that were late received detention

conj

1. Used to introduce a noun clause, or a clause showing reason, purpose, consequence or a result or expressing a wish or desire

Example: He spoke so quickly that I couldn't understand
Example: Oh, that the day would never end!

adverb

1. To the degree or extent shown or understood.

Example: won't reach that far
2. colloq or dialect
To such a degree that; so.
Example: They are that unsociable they never leave the house

Idiom: all that

colloq
Very.
Example: not all that good

Idiom: that's that

That is the end of the matter.

Etymology: Anglo-Saxon thæt.

Info:

Many people think that the relative pronoun that in constructions such as The man that I met happened to be Philip's uncle is informal and should be replaced by who or whom or which in formal contexts. In fact, that used in this way is acceptable in any context, as is the omission of that in The man I met happened to be Philip's uncle.