The article is devoted to the study of the evolution of the lexical meaning of the word taŋara in the Sakha (Yakut) language. The etymology and functioning of the word in the epic text allow us to reveal the following meanings: ‘heaven’, ‘deity’, ‘spirits of aiyy’ and ‘ičči’. The context of the use of the word has changed under the influence of the ideology of the Orthodox dogma. While preserving the external form, the word underwent significant morphological and semantic changes: the affixation method increased the word-formative and phrase-forming potential of the word, the basic meaning of ‘god’ was fixed, the semantic volume expanded, some values reflecting the pagan world view became obsolete. There was a break with the synonym ičči as a designation for otherworldly entities, and aiyy as the name of good spirits remains a component of the name of the Christian Orthodox god Aiyy Taŋara.