I. Unionism BrE AmE noun [uncountable]
the principles of those people in Northern Ireland, mainly Protestants, who want Northern Ireland to remain as part of the UK. There are several political parties that support these principles, including the ↑ Ulster Unionists and the ↑ Democratic Unionist Party . ⇨ compare ↑ republicanism
II. [m2]See main entry: ↑ Unionist