The relevance of the study is conditioned upon the importance of distinguishing the concepts of idiolect, idiostyle, and sociolect in linguistic science, understanding the processes occurring at the border of the terminological field, and using psychological, sociological, and communicative aspects to understand the mechanisms of building these concepts. The purpose of the study is a comparative analysis of linguistic terms based on various criteria, in particular the number of communicants (speakers), social marking or neutrality of the lexical layer, the purpose, conditions, and purposes of the development of certain language layers, the features of the design of lexemes at different levels of the national language (phonological, phonetic, grammatical, morphological, stylistic, syntactic). The main method of research is a theoretical approach to understanding the concepts of idiolect, idiostyle, and sociolect, searching for relationships between them and differences. This study discloses the main intralingual and extralingual factors that contribute to the development, identification, or isolation of these concepts, the features of the coexistence of these terms in contexts with different stylistic content, considers the mechanisms by which the boundaries between these concepts can be outlined, focuses on modern research on the emergence of idiolects, idiostyles, and sociolects. The materials presented in this study will help to further study terminological processes in depth, in particular, contextual and conceptological, global interdisciplinary influences in the national space, mechanisms of isolation and structuring of certain terms to expand or narrow already known meanings.