
An administrative division, unit, entity, area or region, also referred to as a subnational entity, or constituent unit, is a portion of a country or other region delineated for the purpose of administration. Administrative divisions are granted a certain degree of autonomy and are usually required to manage themselves through their own local governments. Countries are divided up into these smaller units to make managing their land and the affairs of their people easier. A country may be divided into provinces, states, counties, cantons or other sub-units, which, in turn, may be divided in whole or in part into municipalities, counties or others.

Regional airlines are airlines that operate regional aircraft to provide passenger air service to communities without sufficient demand to attract mainline service. There are two main ways for a regional airline to do business:As an affiliated airline, contracting with a major airline, operating under their brand name, and filling two roles: delivering passengers to the major airline's hubs from surrounding towns, and increasing frequency of service on mainline routes during times when demand does not warrant use of large aircraft, known as commuter flights. Operating as an independent airline under their own brand, mostly providing service to small and isolated towns, for whom the airline is the only reasonable link to a larger town. Examples of this are PenAir, which links the remote Aleutian Islands to Anchorage, Alaska, and Mokulele Airlines, which operates in the Hawaiian islands.

The Asia-Pacific is the part of the world in or near the Western Pacific Ocean. Asia-Pacific varies in area depending on context, but it generally includes East Asia, South Asia, Southeast Asia, and Oceania.

A consular district is a sub-national region designated by a consular post to exercise consular functions in a host country. A consular district is serviced by a consul or "consul-general" and is headquartered at a consulate or "consulate-general." It is a common utility for spreading diplomatic representation and services to regions of a host country beyond a guest country's embassy in the capital.

A geofence is a virtual perimeter for a real-world geographic area. A geo-fence could be dynamically generated—as in a radius around a point location, or a geo-fence can be a predefined set of boundaries.

Lowell Regio is a region on the dwarf planet Pluto. It was discovered by the New Horizons spacecraft in 2015. The region corresponds to the Plutonian northern polar cap. It is named after Percival Lowell who established the observatory where Clyde Tombaugh discovered Pluto.

Regional organizations (ROs) are, in a sense, international organizations (IOs), as they incorporate international membership and encompass geopolitical entities that operationally transcend a single nation state. However, their membership is characterized by boundaries and demarcations characteristic to a defined and unique geography, such as continents, or geopolitics, such as economic blocs. They have been established to foster cooperation and political and economic integration or dialogue among states or entities within a restrictive geographical or geopolitical boundary. They both reflect common patterns of development and history that have been fostered since the end of World War II as well as the fragmentation inherent in globalization, which is why their institutional characteristics vary from loose cooperation to formal regional integration. Most ROs tend to work alongside well-established multilateral organizations such as the United Nations. While in many instances a regional organization is simply referred to as an international organization, in many others it makes sense to use the term regional organization to stress the more limited scope of a particular membership.