Уперше в лінгвоукраїністиці з’ясовано стан вивчення мови Поділля кінця ХІХ – початку ХХ ст., визначено роль окремого мовно-культурного регіону (ареалу) в розвитку загальнонаціонального літературного стандарту, опрацьовано рукописи, автографи, першодруки С. В. Руданського, А. П. Свидницького та М. М. Коцюбинського, схарактеризовано мову цих джерел, а також мову фольклорних та етнографічних записів із Поділля в контексті розвитку української літературної мови. Констатовано, що основною діалектною базою для мови цих письменників був подільський говір південно-західного наріччя. Автографи, у яких збережені діалектні риси, послугували досить важливими джерелами у вивченні їхнього ідіолекту, оскільки в опублікованих значно пізніше творах ці риси здебільшого знівельовані свідомим утручанням видавців. Простежено характер відображення лексичних одиниць із художніх текстів С. В. Руданського, А. П. Свидницького та М. М. Коцюбинського в лексикографічних працях.
In the work the state of researching the language of Podillia in the late XIX – early XX centuries has been defined, the role of a separate linguistic and cultural region (area) in the development of a national literary standard has been determined for the first time in Ukrainian linguistics. Systematic investigation of the linguistic and cultural area of Podillia, which involved the collecting and studying of ethnographic and folklore materials, began in the first decades of the XIX century and it was carried out by representatives of domestic and Polish science. Till the middle of the XIX century such studies were mainly historical and geographical in nature, ethnographic descriptions in the publications of this period occupied a relatively small place. From the second half of the XIX century the next stage in the ethnographic studying of Podillia begins, which resulted in accumulation of a significant amount of factual material, mainly on the spiritual culture of Podillia – customs and rituals of family and calendar cycles, folk demonology, fairy tales, songs, riddles, proverbs and sayings that reflect Podillian dialect features. Folklore and ethnographic records from Podillia were and still are an important source of historical studying of Podillian dialects. Their features are partially reflected in the records of K. Sheikovskyi, A. Dyminskyi, K. Shyrotskyi, S. Rudanskyi, A. Svydnytskyi, and others. In the analyzed folklore texts from Podillia many dialect elements have been recorded, they remain till nowadays. Manuscripts / autographs / first editions of works by S. Rudanskyi, A. Svydnytskyi and M. Kotsiubynskyi have been studied and their language has been characterized in the context of the Ukrainian literary language history formation and development. The analysis of the manuscript heritage of Podillian writers gives grounds to state that the main dialect base for their language was the Podillian dialect of the south-western dialect. Autographs, in which dialectal features are observed, serve as extremely important sources in the study of their individual linguistic style. Comparing the manuscript heritage with lifetime editions convinces that autographs, in which dialectal features are observe, remain extremely important in studying of their individual linguistic style, because in the works published much later these features have been removed. Researching of the language of the works of Podollian writers on the basis of authentic texts, but not on the basis of works of different years of publication, gives grounds to expand the list of linguistic features presented in works on the history of the Ukrainian literary language. The character of lexical units’ reflection in literary texts by S. Rudanskyi, A. Svydnytskyi and M. Kotsiubynskyi in lexicographic works has been traced. n dictionaries of the Ukrainian language, starting from the second half of the XIX century and up to nowadays, there are vocations to their works. Part of the vocabulary they used has been codified in dictionaries and reference books and became commonly used, another – belongs to the historical fund, the third is recorded as dialectal, and the fourth is not recorded in modern explanatory dictionaries at all and exists only in oral speech.