The Collaborative International Dictionary
irredentism \irredentism\ n. the doctrine that irredenta should be controlled by the country to which they are ethnically or historically related.
Syn: irridentism.
Wiktionary
n. A doctrine advocating annexation of foreign lands by a country with historic or ethnic links.
WordNet
n. the doctrine that irredenta should be controlled by the country to which they are ethnically or historically related [syn: irridentism]
Wikipedia
Irredentism (from Italian irredento for "unredeemed") is any political or popular movement intended to reclaim and reoccupy a "lost" or "unredeemed" area; territorial claims are justified on the basis of real or imagined national and historic (an area formerly part of that state) or ethnic (an area inhabited by that nation or ethnic group) affiliations. It is often advocated by nationalist and pan-nationalist movements and has been a feature of identity politics and cultural and political geography.
An area that may be subjected to a potential claim is sometimes called an irredenta. Not all irredentas are necessarily involved in irredentism.
Usage examples of "irredentism".
And this lack of old-style irredentism and expansionism reflects not only ideology, international reality and contemporary culture but also prudence and the strong and bitter historical memories which permeate European society.