Which term refers to a region or country that is significantly influenced but not governed by another state?

The term "sphere of influence" refers to a region or country that is significantly influenced by another state, without being formally governed by it. This influence can manifest in various ways, such as economic, political, or military pressure. The country within the sphere of influence may maintain its sovereignty, but its policies and international relations are often shaped by the dominant country's interests.

For example, during the 19th and early 20th centuries, several powerful nations had spheres of influence in regions like China, where they exerted control over trade and military presence without outright governing those areas. This arrangement allows for significant external influence while still allowing the influenced state to retain some level of autonomous governance.

The other terms provided each have distinct meanings. A satellite state typically denotes a country that is formally under the political control or influence of another nation, often seen in the context of Cold War Europe. A protectorate refers to a territory that maintains its own government but is under the protection and control of a more powerful state, implying a strong level of governance. A vassal state indicates a relationship where one state is subordinate to another, often in a feudal context, which implies dependence and lack of full autonomy.