This is the 8624th most frequent Russian word.
осетия
Ossetia: A region in the Caucasus, divided into North Ossetia (part of Russia) and South Ossetia (a disputed territory).
Here, 'Осетия' is used as a proper noun to denote a region.
Осе́тия располо́жена в северной части Кавказских гор.
Ossetia is located in the northern part of the Caucasus Mountains.
In this example, 'Осетию' is the accusative form of 'Осетия,' used as the object of the verb.
Я планирую поездку в Осетию на следующей неделе.
I am planning a trip to Ossetia next week.
In this context, 'Осетии' is the genitive form of 'Осетия,' showing possession or association with the noun 'Южной.'