The theme of the article is the concept of credentials based on the data from general and terminological dictionaries. It contains a proposal for a Russian-Polish entry article with the name of this diplomatic document (entry article as a part of a translation dictionary within the project “Diplomacy and politics. Russian-Polish dictionary survey”). The author explains the history of this term in both languages, focusing on the dissimilarity of its grammatical form both in Russian and Polish monolingual and bilingual dictionaries, which is especially visible while comparing dictionary and textual data. The material derived from Russian and Polish parallel texts (autonomous, independent of each other) is described according to the recommendations adopted for translation dictionaries – providing their users with the practical information on the usage of units (their syntactic requirements and usage conditions). The analysis also devotes ample attention to the socalled undescribed translated items (equivalents not recorded so far in Russian-Polish/ Polish-Russian lexicography). The discussion of numerous bilingual dictionaries justifi es the claim that a considerable part of collected units can be regarded as undescribed translated items (undescribed equivalents).