Etymology and terminology
The 1707 Acts of Union declared that the kingdoms of England and Scotland were "United into One Kingdom by the Name of Great Britain", though the new state is also described in the Acts as the "Kingdom of Great Britain", "United Kingdom of Great Britain" and "One Kingdom".[note 12] The term "United Kingdom" is found in use as a description, but not a name, during the 18th century, and the country has occasionally been referred to in later centuries as the "United Kingdom of Great Britain" although its full official name, from 1707 to 1800, was simply "Great Britain", without a "long form". The Acts of Union 1800 united the Kingdom of Great Britain and the Kingdom of Ireland in 1801, forming the United Kingdom of Great Britain and Ireland. Following the partition of Ireland and the independence of the Irish Free State in 1922, which left Northern Ireland as the only part of the island of Ireland within the United Kingdom, the name "United Kingdom of Great Britain and Northern Ireland" was adopted.
Although the United Kingdom, as a sovereign state, is a country, England, Scotland, Wales and, to a lesser degree, Northern Ireland are also regarded as countries, though they are not sovereign states. Scotland, Wales and Northern Ireland have devolved self-government. The British Prime Minister's website has used the phrase "countries within a country" to describe the United Kingdom. Some statistical summaries, such as those for the twelve NUTS 1 regions of the United Kingdom, also refer to Scotland, Wales and Northern Ireland as "regions". Northern Ireland is also referred to as a "province". With regard to Northern Ireland, the descriptive name used "can be controversial, with the choice often revealing one's political preferences".
The term "Great Britain" refers conventionally to the island of Great Britain, or politically to England, Scotland and Wales in combination. However, it is sometimes used as a loose synonym for the United Kingdom as a whole. GB and GBR are the standard country codes for the United Kingdom (see ISO 3166-2 and ISO 3166-1 alpha-3) and are consequently used by international organisations to refer to the United Kingdom. Additionally, the United Kingdom's Olympic team competes under the name "Great Britain" or "Team GB".
The term "Britain" is used both as a synonym for Great Britain, and as a synonym for the United Kingdom.
Usage is mixed, with some organisations including the BBC and British Government preferring to use Britain as shorthand for Great Britain. While the UK Permanent Committee on Geographical Names (whose definitions are the "authoritative geographical names of the United Kingdom") lists "United Kingdom" and "UK or U.K." as shortened and abbreviated geopolitical terms for the United Kingdom of Great Britain and Northern Ireland, but does not list "Britain", it has been used "informally" by government websites.
The adjective "British" is commonly used to refer to matters relating to the United Kingdom. The term has no definite legal connotation, but is used in law to refer to United Kingdom citizenship and matters to do with nationality. People of the United Kingdom use a number of different terms to describe their national identity and may identify themselves as being British; or as being English, Scottish, Welsh, Northern Irish, or Irish; or as being both.
In Welsh, the long form name of the state is "Teyrnas Unedig Prydain Fawr a Gogledd Iwerddon", with "Teyrnas Unedig" being used as a short form name on government websites. However, it is usually abbreviated to "DU" for the mutated form "Y Deyrnas Unedig". In Scottish Gaelic, the long form is "Rìoghachd Aonaichte Bhreatainn is Èireann a Tuath" and the short form "Rìoghachd Aonaichte".