Answer:
Separation of power
Step-by-step explanation:
Separation of power is a form of governance in which power is distributed among the various branches of the government, each having independent, separate powers and responsibilities. It prevents the power of one branch from getting in conflict with other branches. It prevents any one branch from getting too powerful because it prevents any one branch from performing the core functions.
United States and United Kingdom follows the tripartite system, in this system there are three main branches of government: the legislative branch, executive branch and the judicial branch. The term " separation of powers" was coined by Montesquieu in 18th century.