Wewior (Polish) comes from Polish wiewiór, from Polish Wiewiórka, from Proto-Slavic věverъka, from Proto-Slavic *vě̀verь, from Proto-Balto-Slavic wēweris, from Proto-Indo-European wēr-, from Proto-Indo-European wer- — to burn; to cover, heed, notice; squirrel.