The Latin-Russian-German lexicon called Nomenclator, published by Elias Kopijevski in Amsterdam in 1700, has a well-established position in the research on Russian lexicography. However, few scholars studying the history of the Russian language are aware of the existence and depository of two later substantially revised and extended versions of Nomenclator, published in St Petersburg in 1718 and 1732. The fact that the Amsterdamian Nomenclator contains besides numerous Polish loans also borrowings from Belorussian and Ukrainian has frequently been commented on, mostly in connection with the attempts to determine the nationality of Kopijevski (Илья Копиевский), who was considered to be Polish by some researchers and Belorussian by others. Nevertheless, these endeavours were usually confined to listing several (or, at best a dozen or so) lexemes of non-Russian (i.e. either Belorussian or Ukrainian) origin. Belorussian and Ukrainian borrowings are a central issue in the present article, which attempts to identify and systematize the entire West Ruthenian (i.e. Belorussian and Ukrainian) vocabulary of Nomenclator, dividing it into two major sets: (a) non-native and (b) native.The author also addresses the question of how much Kopijevski’s Nomenclator owes to Johann Biber’s Nomenclator selectissimas rerum appellationes tribus linguis, Latina, Germanica, Polonica explicatas indicans, and more precisely to its Polish part, written by Petrus Artomius Krzesichleb.