This is the 844th most frequent Russian word.
та
The Russian word "та" means "that" (feminine singular).
The word 'та' is used as a demonstrative adjective meaning 'that', referring to a feminine singular noun (книга).
Та книга была очень интересной.
That book was very interesting.
Here 'ту' is the accusative form of the demonstrative pronoun 'та', used to specify a feminine singular object.
Я встретил ту женщину, о которой ты говорил.
I met the woman you were talking about.
In this sentence, 'ту' again appears in the accusative case, functioning as a demonstrative adjective specifying 'истину' (truth).