Which term describes a region under U.S. jurisdiction?

The term that describes a region under U.S. jurisdiction is "Territory." In a legal context, a territory refers to a specific area that is governed by the United States but is not considered a state. It can include regions that have distinct forms of self-governance or are directly administered by the federal government. Examples of U.S. territories include Puerto Rico and Guam.

States are defined as political entities that have their own governments and are part of the United States. They possess full sovereignty within their borders but are distinct from territories. Provinces typically refer to administrative divisions within countries like Canada, and therefore do not apply to the context of U.S. jurisdiction. A district can refer to specific areas within states or territories but does not encompass the broader definition of a jurisdictional region like a territory does.

Thus, the correct understanding of jurisdiction under U.S. law aligns with the definition of a territory.