The article deals with the etymological analysis of Russ. dial. ancutka 'devil, demon; Antichrist; hobgoblin, water-sprite, familiar, sylvan; trollop; poor person; pickle; curse'. Being based on the made lexeme analysis, Russ. dial. ancutka is explained as primordially Russian (!!!) word, which contrarily V. N. Toporov's hypothesis by no means could be compared with the water space birds names. Due to such decision it can not be explained as Baltism either. By virtue of it, determination of the Protobaltic tribes presumptive borders of their residing territory in Russia, according to areal distribution of the word, is not possible.