A system in which one level of government exercises an overwhelming authority over others can best be described as

A system in which one level of government exercises an overwhelming authority over others can best be described as a unitary system. In a unitary system, the central or national government holds most of the power and authority, and it delegates some of the powers to the lower levels of government such as regional or local governments. The national government has the power to create, merge or abolish local governments, and it can also control the budgets and policies of those lower levels of government. This is in contrast to a federal system where the powers are shared between the national and lower levels of government, and each level has its own area of authority.