This is the 8232nd most frequent Polish word.
osobowych
"Osobowych" means "personal" or "passenger" (depending on context, e.g., personal data or passenger cars).
Here, 'osobowy' modifies 'pociąg' (train) to specify the type of train, indicating it is intended for passengers rather than cargo.
Pociąg osobowy odjechał pięć minut temu.
The passenger train departed five minutes ago.
In this sentence, 'osobowy' describes 'samochód' (car), specifying that it is a standard passenger car, as opposed to a sports car or a utility vehicle.
Muszę kupić ubezpieczenie dla mojego samochodu osobowego.
I need to purchase insurance for my passenger car.
Here, 'osobowych' pertains to 'danych' (data), providing information about the type of data, indicating that it is related to an individual person.