This is the 10833rd most frequent Polish word.
dziesiątą
The Polish word "dziesiątą" means "tenth" in English (feminine accusative or instrumental form).
Here, 'dziesiątą' is used to denote the time, specifically the tenth hour, in the accusative case because it follows the preposition 'o' which dictates this case.
Spotkamy się o dziesiątą rano.
We will meet at ten o'clock in the morning.
In this context, 'dziesiątą' is used as an ordinal numeral describing the sequence (the tenth page) and is in the accusative case because it's the direct object of the verb 'Przeczytałem'.
Przeczytałem dziesiątą stronę książki.
I read the tenth page of the book.
Here, 'dziesiątą' is an ordinal numeral used to describe a fractional portion (the tenth part) and is in the accusative case, following standard agreement in attributive situations.