Русско-англо-русский юридический словарь

The separation of powers, often imprecisely used interchangeably with the trias politica principle, is a model for the governance of a state (or who controls the state). The model was first developed in ancient Greece. Under this model, the state is divided into branches, each with separate and independent powers and areas of responsibility so that the powers of one branch are not in conflict with the powers associated with the other branches. (Wikipedia)

Authoritarianism is a form of government characterized by the rejection of political plurality, the use of a strong central power to preserve the political status quo, and reductions in the rule of law, separation of powers, and democratic voting. (Wikipedia)