The Lituanistic lexicographic source stored in the Clementinum and dating back to the third and fourth decades of the 18th century found its way to the academic environment of Vienna-Prague no later than in 1777. The Austrian history of the Prague manuscript of the German - Lithuanian dictionary between the periods of 1777-1861 is analysed in the article.
It is attempted to identify the owners of the dictionary alongside with the researchers - 'users'. The question why and under what circumstances the dictionary appeared in Vienna and later in Prague, and what significance it contained is raised.