Abstract
The study is aimed at a complex analysis of cognitive factors that influence the meaning and functional features of the eponym. To determine the specific characteristics of eponymic terms, the authors carry out a diachronic analysis of eponymic vocabulary and analyze the evolutionary changes in the components of the term. The authors establish the significance of the influence that ideosemantics of proper nouns has over the meaning and functioning of terminological units and the sources of proper nouns. In linguistics, eponym means a terminological word combination where a proper noun is a component. It can be concluded that terms stem also from geographical names, mythological and biblical characters.