The subject matter of this article is semantical-motivational and linguogeographical peculiarities of Northern Russian splanchnonyms - lexical units naming internal organs (from Greek алМухуа (splanchna), meaning ‘viscera’). The author focuses on the interconnection and overlapping of the names of human viscera and splanchnonyms related to animals. This issue is discussed in the first part of the article. The author notes that splanchnonyms related to humans tend to be secondary in terms of their origin, i.e. to be derivatives of the names of animal viscera. The paper reveals extralinguistic reasons for the language attention of dialect speakers to animal viscera - fishing and hunting, cooking of meat dishes. The second part of the paper includes an overview of splanchnonyms related to animals; overlapping of the relevant cookery and somatic vocabulary is noted; the complexity of the ideographic structure of the vocabulary in question is identified, main ideograms with the words they comprise are listed. The difference between the names of internal organs of livestock and those of fish is shown. Special attention is paid to linguogeographical features of splanchnonyms related to fish: the relevant vocabulary is noted in the zone of contacts with the Finno-Ugric peoples and is characterized by fractional semantic differentiation. In the final part of the article, the author cites particular motivational features characteristic of the words naming animal viscera. The paper also considers metaphorical names, including both splanchnonyms motivated by the names of everyday realities and lexical units related to daily routines that were secondary formed from splanchnonyms. The lexical realization of the motivational transition ‘waste’ - ‘internal organs’ is analyzed.