Wikipedia
Brännvin (or brændevin in Danish, brennevin in Norwegian, brennivín in Faroese and Icelandic and (palo)viina in Finnish) is the Swedish version of the general Scandinavian term for liquor distilled from potatoes, grain, or (formerly) wood cellulose; both of flavored and unflavored variants. The term includes vodka and akvavit, but akvavit is always flavored.
Beverages labelled brännvin or viina are usually unflavored and have an alcohol content between 30% and 38% ABV. European Union regulations reserve the name " vodka" for beverages distilled to at least 95% ABV and bottled at 37.5% or higher. In Finland, the word viina is always used for Finnish-made neutral spirit, including Finnish vodka, and the Russian word (vodka) is used only for vodkas from other countries. In informal speech, viina can also refer to any similarly strong beverage similarly to booze, whether flavored or unflavored.
The term "vodka" was not used for Swedish vodkas before 1958.
The word brännvin means "burn-wine"; the Finnish equivalent (palo)viina means "burnt liquor." (Sometimes the distillation of beverages is called "burning.") It is cognate with English brandy, Dutch brandewijn, German Branntwein, and Icelandic brennivín.