This is the 9643rd most frequent Polish word.
władywostoku
"Władywostoku" is the genitive or locative form of "Władywostok," which is the Polish name for Vladivostok, a city in Russia.
Here 'Władywostok' is used as a proper noun referring to the specific city.
Władywostok jest miastem w Rosji.
Vladivostok is a city in Russia.
In this sentence, 'Władywostoku' is in the locative case, used after 'do' to indicate a direction towards the city.
Podczas podróży do Władywostoku odwiedziłem kilka zabytków.
During my trip to Vladivostok, I visited several landmarks.
Here, 'Władywostoku' is in the genitive case, indicating possession or association (history of Vladivostok).