This article provides an etymological commentary on the geographical terms tundra and rada which characterize Northern Russian terrain. Tundra now belongs to the standard language whilst rada is a dialectal word only known in Pomor dialects. The first part of this article is devoted to the word tundra, providing a number of clarifications and commentaries on its etymology developed earlier by J. Kalima, M. Vasmer and E.A. Anikin. The principal clarification is that the main source of borrowing for the Russian word tundra is not Finnic languages, but rather Eastern dialects of Sami languages. According to the author of this article, the way of semantic development of tundra (from its primary meaning ‘mountain’ in Pomorye to ‘lowland’, ‘plain’ in Siberia) can serve as a model for etymological analysis of some other Northern Russian landscape terms. This possibility is illustrated in the second part of this article, which is devoted to the geographical term rada...