The present article is dedicated to the study of interlingual contacts based on the facts given by the history of the Hungarian personal suffix -as. This suffix is used in modern Serbian, Croatian, Yugoslav-Ruthenian, Slovenian and Slovak literary languages and dialects. People speaking these dialects have been living for a long time in these territories that used to be a part of the Hungarian kingdom. The history of this suffix, its functioning and its present status is demonstrated on the basis of Carpathian and Ruthenian written old and new texts. The productivity of the borrowed personal suffix -?? (-??) is considered to be a result of active interlingual contacts in the Carpathian region and also of the considerable influence of Hungarian on the language and culture in the Southern Carpathian hills. There are many words in modern Carpatho-Rusyn texts which are borrowed from Hungarian, e.g.: ???????, ??????, ??????, ??????, ??????, ????????? etc. Some of them appear in word formation paradigms of the Carpatho-Rusyn motivated words, e.g.:????????, ????????????, ????????, ???????, ??????, ??????? and so on. The result of the Carpatho-Rusyn and Hungarian language contacts on word formation level testifies to a very intensive interaction. In modern Ruthenian the same tendency is to be observed: numerous lexical borrowings from Hungarian exist side by side with borrowings of units on a more abstract level. In our case the word formation suffix ?? (-??) with a personal meaning is of Hungarian origin and it is very productive in modern Carpatho-Rusyn.