More than 70 years ago, the well-known dictionary of selected Indo-European synonyms by C.D. Buck was published. It represents an important work in the field of comparative lexicology and semantic reconstruction. It is structured according to the ideographic principle and covers 22 thematic groups, reflecting various aspects of human life, nature, and abstract concepts. The dictionary is far from being exaustive, as not all Slavic data were included; only Serbo-Croatian, Czech, Polish, Russian, and Old Church Slavonic were represented. The authors make a cause for why it is necessary to create a new ideographic dictionary of Slavic vocabulary, constructed in accordance with the principles of Buck's work, but including data from all Slavic literary languages (Russian, Ukrainian, Belarusian, Polish, Kashubian, Upper Sorbian, Lower Sorbian, Czech, Slovak, Bulgarian, Macedonian, Serbian, Croatian, Slovenian, Old Church Slavonic), as well as a number of neighbouring languages (Lithuanian, Romanian, Albanian, Greek, Hungarian). Unlike Buck's dictionary, a more detailed semantic and etymological analysis of Slavic vocabulary is envisioned. A number of errors made by Buck in the collection of Slavic material are demonstrated. The tasks and theoretical foundations of the new dictionary are defined, and examples of dictionary entries for "World", "Man", and "Father-in-law (father of the wife); Father-in-law (father of the husband)" are provided.