Kaliningrad
Italy is separated from the rest of Europe by the Alps.
The Alps separate Russia from the rest of Europe.
The Province of Cabinda.
A part of a country separated from the rest of its nation is called an enclave or exclave, depending on whether it is fully surrounded by foreign territory or connected to the main country by land.
It is the country's chief port through which products come for the rest of the country.
It is the country's chief port through which products come for the rest of the country.
If you want a meaningful answer to that question you should specify which country you are asking about.
Depending on the context, it could be a territory or a colony.
Polish Corridor
A value separated from the rest of the data is called an outlier
In Russian, "Отдых в мире" means "Rest In Peace".
In Russian, "Отдых в мире" means "Rest In Peace".