Abstract
Appellated toponyms in Bulgarian language are under the focus of the present investigation and comparisons with other languages have been drawn (Russian, Czech, English) in it. Some of the most characteristic cases of deriving common nouns from proper names by means of word-formation formants have been selected and discussed.
The thematic classification of the excerpted material presented in the work provides for tracing both the mechanisms and word-formation models enabling with the transition of a proper name into a common noun, for finding out the similarities and differences between the compared languages, as well as for clearing both the ways of penetration of toponyms into a particular language system in the form of foreign realia and of their assimilation and functioning there.