What can serve multiple purposes and may be either functional or geographic in nature?

The concept that can serve multiple purposes and may be either functional or geographic in nature is best represented by branches. In the context of various fields, a branch can refer to a division of an organization that handles specific functions, such as marketing or finance, while also implying geographical distinctions, such as a branch office located in different cities or countries. This duality allows branches to represent both the organizational structure and the distribution of services across different areas, making them versatile and essential to understanding how entities operate.

Units could indicate specific components within a system or organization but do not inherently imply the geographic aspect. Cells generally refer to smaller, often interchangeable parts of a larger structure and are less commonly associated with geographic contexts. Divisions are similar to branches but typically suggest a more formal separation that might not encompass both functional and geographic aspects equally. Therefore, branches uniquely encapsulate the dual functionalities sought in the question.