The article elaborates the basic features of the system of semi-presidential government, which was popularized by Maurice Duverger as a ”new model of the political system“. The diversity of individual definitions of semi-presidential government and their shortcomings indicate a lack of consensus on the fundamental features of the system, which in turn allows individual political systems to be viewed as either parliamentary or semi-presidential, depending on the features used in individual definitions. Based on the analysis of the original semi-presidential models (Weimar Constitution, the Constitution of the French Fifth Republic), the paper seeks to elaborate a more comprehensive definition of semi-presidential government as a system of presidential domination in the political system. In this sense, this system is defined as a system in which 1. the president is elected directly by the citizens, i e indirectly by an electoral college in which a representative body does not dominate or is excluded from it; 2. his term of office may not be terminated by a political decision of the representative body; 3. he is the actual head of the executive and performs it personally and through the government proposed by him to the parliament and 4. the basis of his key position within the executive are certain constitutional prerogatives (dissolution of parliament, appointment, and dismissal of the government) and / or leadership position in the party / a party coalition that has a majority in parliament.