Orangism is a form of royalistic loyalty to the House of Orange-Nassau of the Netherlands. Most people in the Netherlands are Orangists (only 15% of them want a republic and no significant group supports another house).
Orangism is also the name of a political current in Belgium, especially in Flanders that never really wanted to be separated from the Netherlands, and Luxembourg. Orangists' aim is to restore the House of Orange-Nassau on the throne of Belgium and Luxembourg, and this Orangist movement is largely inspired by the restoration of the United Kingdom of the Netherlands (see Whole-Netherlands) or the reunification of Flanders and the Netherlands (see Greater Netherlands).
The movement has a relatively significant support among certain Flemish intellectual circles in Belgium but their effect in the Netherlands is confined to some individuals, particularly of conservative leanings.