The article attempts to describe the way of storing and functioning of meanings of pol-ysemous words in the linguistic lexicon. To achieve this goalwe turned to research of semantic primitives discovered in the course of lexical analysis. Within the framework of the interdisci-plinary approach to the problems of words meanings ambiguity, the article justifies the hypoth-esis that in the process of polysemous words decoding the communicant does not take into account all semantic components of a word. The article aims at confirmation the functioning of a polysemous word meaningful core –lexical invariant, consisting of the clusters of the most essential semantic components. We provide theoretical and practical reasons for semantic in-tegrity of polysemous words meanings on the basis of the invariant theory. Basic methods in-clude invariant analysis of figurative meanings based on cognitive images, and component analysis of dictionary definitions. The invariant cluster as a set of the most essential and stable semantic components is eventually formed in the consciousness of a native speaker in accord-ance with the intuition of an average native speaker.