The present study is carried out in the course of cognitive word formation of the Russian language. The author, noting the axiological nature of word formation, pays close attention to the internal (propositional-semantic) organization of the same root word families - one of its complex units. The object of study in the work are the same root word families with the vertex components otets , papa , each of which demonstrates the angles of understanding of the culturally significant fragment of the world in the minds of the Russian people. The source of the same-root vocabulary selected for the analysis within two families are the dictionary materials. Reference to lexicographic works and application of the method of propositional-frame modeling allow, firstly, to establish a set of same-root lexemes, united by the vertices otets , papa ; secondly, to determine the semantic volume and word-formation capabilities of the vertex components otets , papa ; thirdly, to trace the features of the implementation of multidimensional semantics of the vertex components otets , papa in the semantic structure of same-root derived lexemes within the boundaries of the considered families through identification of propositional structures. It is established that the propositional-semantic organization of families of same-root words is set by the meaning-generating potential of the top components and highlights the actual, culturally significant, aspects of the perception of father in the consciousness of the Russian people. It is concluded that the same-root lexemes within the comparative families reveal different semantic specialization, which reflects the system of knowledge and ideas of modern Russian speakers.