The article offers a comparative analysis of a number of concepts, ‟atto”, ‟azione”, ‟attività”, ‟comportamento” in the Italian language, and their justification in the structure of the category of relations in the cultural linguistics environment of the Italian language in comparison with similar concepts in the cultural linguistics environment of the English language. The analysis was carried out using the dictionary definitions method, which made it possible to analyse the semantic structure of words, as well as the method of comparative analysis to determine the similarities and differences of the studied lexemes in Italian and English languages. The study assumed consideration of these concepts in a combination of cognitive and cultural linguistics approaches. This combination is due to topicality of comparative studies in the dynamic development of the study of problems of intercultural communication as a challenge of modernity. In the course of a comprehensive analysis, the similarities and differences of the compared concepts were revealed in two cultural linguistics environments of almost totally unrelated languages. The result of the study of the semantic structure of the lexemes ‟atto”, ‟azione”, ‟attività”, ‟comportamento” is supposed to create the basis for further studies of the semiotics and axiology of verbal expressions of the complex concept of ‟behaviour” in the system of interpersonal and social relations.