A language is a system, in which a number of partially overlapping subsystems can be distinguished, which in the works of various linguists are called sublanguages or sublanguages. The specific term in relation to the term "sublanguage" is the term "special sublanguage", which is used to refer to language means used in communication (both official and unofficial) on scientific and professional topics. In domestic linguistics, there is currently no single opinion on the number of types of special vocabulary and the established terminology for their nomination. The codified subsystem of specialized vocabulary is traditionally called terminology. When nominating its non-codified subsystem, terms such as professional jargon, slang, professional vocabulary, professional dialect is used, which often replace each other or receive ambiguous, sometimes mutually exclusive definitions.