This is the 45th most frequent Czech word.
tam
"Tam" means "there" in English.
Here, 'tam' specifies a location where the book is found, typically indicating 'there' or 'in that place'.
Tam je moje kniha.
There is my book.
In this case, 'tam' indicates a direction or destination, meaning 'to that place' or 'there'.
Půjdeme tam zítra.
We will go there tomorrow.
Here, 'tam' situates the context of the statement, referring to a specific location where the weather is being described.