- a division of the United Kingdom located on the northern part of the island of Ireland
- A province of the United Kingdom that occupies the northeastern part of Ireland, comprised of six counties of Ulster; pop. 1,570,000; capital, Belfast. It was established as a self-governing province in 1920, after refusing to be part of the Irish Free State. Domination by the Protestant majority and discrimination against the Roman Catholic minority led to violent conflicts and, from 1969, British army units were present in an attempt to keep the peace. Terrorism and sectarian violence by the Provisional IRA and other paramilitary groups, both Republican and Loyalist, resulted in the imposition of direct rule from London in 1972. Multi-party talks begun in 1996 led to an agreement between most political parties in 1998. In 1999, a devolved parliament was inaugurated, with representation from both Nationalist and Unionist groups
- Northern Ireland is a constituency of the European Parliament. It currently elects three MEPs using the Single Transferable Vote, the only United Kingdom constituency to do so.
- Office is the nerve-centre of British government administration in Northern Ireland. Until recently, it was responsible for the running of all government departments in Northern Ireland.