This is the 9677th most frequent Polish word.
zachodnia
"Zachodnia" means "western" in English.
In this sentence, 'zachodnia' is used as an adjective describing the part of Poland (the western part).
Polska zachodnia graniczy z Niemcami.
Western Poland borders Germany.
Here, 'zachodnia' acts as an adjective referring to the west-facing side of the building.
Strona zachodnia budynku jest bardziej nasłoneczniona.
The western side of the building gets more sunlight.
In this sentence, 'zachodnia' is used as an adjective describing 'philosophy' with its origin or characteristic, specifically originating from the West.