This meaning refers to areas that are considered part of the country, as opposed to overseas territories or colonies. It is often used in discussions about national policy or cultural identity.

This usage refers to areas that are away from the coast or outer boundaries of a country, typically relating to geography and topography.

This meaning emphasizes Japan as the core of the nation, distinguishing it from territories acquired elsewhere. It often reflects a sense of belonging and cultural identity.

This usage specifies the primary landmass of Japan, as opposed to its various islands and territories. It is used in geographical discussions.