In the paper a new phenomena of language game is analyzed. Its most typical characteristics are elaborated: it functions over linguistically and strictly linguistically as well that could be seen by the examples from the observed Slavic languages Bulgarian, Russian, Polish). Language game could be a test for linguistic synonimy (considerede widely) and for linguistic rules based on the language standard. At the same time it demonstrate specifics of the very language, the productivity of their elements in the system and their frequency in the composing of the new language units.