The "Treasury" of the Old Slavonic language. Book review: Shulezhkova, S.G. (ed.) (2020–) Bol'shoy frazeologicheskiy slovar' staroslavyanskogo yazyka [Large Phraseological Dictionary of the Old Church Slavonic Language]. In 5 volumes. Vol. 1 (2020), 552 p.; Vol. 2 (2022), 560 p.; Vol.

The article considers a multi-volume edition of the phraseological dictionary of the Old Slavonic language. The publication is an event not only in the field of lexicography, but also in the field of studying the historical phraseology of the Slavonic languages - the phraseology of one of the ancient literary languages of Europe. The reviewer identifies the specifics of the dictionary's content, scientific approach to describing the phraseological layer of the first written language of the Slavs, principle of selecting text sources, entry structure, as well as its linguistic and cultural and linguistic didactic vectors. It is concluded that a dictionary of this kind is an innovative dictionary of the diachronic type, with a multi-vector scientific potential for Slavists, phraseologists, language historians, cultural scientists, ethnographers and other specialists studying the Old Slavonic language as a literary language. The author declares no conflicts of interests.