Gulf of Bothnia

The Gulf of Bothnia (Finnish: Pohjanlahti; Swedish: Bottniska viken, i.e. Bottenviken + Bottenhavet) is the northernmost arm of the Baltic Sea. It is situated between Finland's west coast and Sweden's east coast. In the south of the gulf lie the Åland Islands, between the Sea of Åland and the Archipelago Sea.

Bothnia is a latinization. The Swedish name "Bottenviken" was originally just "Botn(en)" with botn being Old Norse for "gulf" or "bay"; which is also the meaning of the second element "vik".

The name botn was applied to the Gulf of Bothnia as Helsingjabotn in Old Norse, after Hälsingland, which at the time referred to the coastland west of the gulf. Later, botten was applied to the regions Västerbotten on the western side and Österbotten the eastern side ("East Bottom" and "West Bottom"). The Finnish name of Österbotten, Pohjanmaa, or "Pohja"-land, gives a hint as to the meaning in both languages: the meaning of pohja includes both "bottom" and "north." Pohja (bottom) is the base word for north, pohjoinen, with an adjectival suffix added.

Botn/botten is cognate with the English word bottom, and it might be part of a general north European distinction of lowlands, as opposed to highlands, such as the Netherlandic region, Samogitia (Lithuanian), and Sambia (Russia).

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