The text «Hellenic and Roman Chronicle» contains about 4,5 thousand nouns in 35 thousand uses. The volume of a material and a thematic variety allow revealing an objective picture of rate of nouns not only in a monument, but also in language of the 15th century. A large number of rare words is present because at the heart of the text translations lie. Words are classified depending on that, they are rare only for this text or are absent in historical dictionaries.