Mainland is defined as "relating to or forming the main part of a country or continent, not including the islands around it [regardless of status under territorial jurisdiction by an entity]." The term is often politically, economically and/or demographically more significant than politically associated remote territories, such as exclaves or oceanic islands situated outside the continental shelf.
In geography, "mainland" can denote the continental (i.e. non-insular) part of any polity or the main island within an island nation. In geopolitics, "mainland" is sometimes used interchangeably with terms like metropole as an antonym to overseas territories. In the sense of "heartland", mainland is the opposite of periphery. In some language a separate concept of "mainland" is missing and is replaced with a "continental portion".
The term is relative: in Tasmania, continental Australia is the mainland, while to residents of Flinders Island, the main island of Tasmania is also "the mainland", although the geological Australian continent includes all the former plus the island of New Guinea and all the smaller islands (e.g. the Torres Strait Islands) in between.
Prominent usages of the term mainland
Continental
This list denotes prominent usages of the term "mainland" to distinguish the islands of a continent from the mainland of a continent through a geopolitical lens.
Mainland Africa, from the perspectives of Cape Verde, Comoros, Madagascar, Mauritius, São Tomé and Príncipe and Seychelles, as well as Mayotte (France) and Réunion (France) Mainland Asia, from the perspectives of Bahrain, Brunei, Cyprus (inc. Akrotiri and Dhekelia and Northern Cyprus), East Timor, Indonesia, Japan (inc. Okinawa Prefecture), the Maldives, the Philippines, Singapore, Sri Lanka, and Taiwan (inc. Kinmen, the Matsu Islands, and Penghu), as well as the Andaman and Nicobar Islands (India), Christmas Island (Australia), the Cocos (Keeling) Islands (Australia), Coloane and Taipa (Macau), East Malaysia (Malaysia), Hainan (China), Hong Kong Island (Hong Kong), Islands District (Hong Kong), Jeju Island (South Korea), Lakshadweep (India) and Sakhalin Oblast (Russia) In the future, if the Salwa Canal is built, also from the perspective of Qatar Mainland Europe, from the perspectives of Cyprus, Iceland, Ireland, Malta, the United Kingdom (inc. Guernsey, the Isle of Man, and Jersey), as well as Åland (Finland), the Faroe Islands (Denmark), Jan Mayen (Norway), Svalbard (Norway), Corsica (France), Sardinia (Italy), Sicily (Italy), Danish islands (Denmark), Azores (Portugal), Madeira (Portugal), Canary Islands (Spain), Balearic Islands (Spain), Gotland (Sweden), Estonian islands (Estonia), Greek islands (Greece) and Russian islands (Russia) Also note that several European countries possess colonies or outposts all around the world (often small islands) in all other continental regions including North America, South America, Africa, Oceania, Asia and Antarctica Mainland Europe, from the perspective of Scandinavia, a peninsula Mainland Southeast Asia, from the perspective of Maritime Southeast Asia
Internal
This list denotes prominent usages of the term "mainland" to distinguish between distinct regions within a single country based on an "islands-to-mainland" relationship. Note that the "mainland" can sometimes consist of a large island rather than a continental landmass.