irredenta

noun

ir·​re·​den·​ta ˌir-i-ˈden-tə 

variants or less commonly irridenta

: a territory historically or ethnically related to one political unit but under the political control of another

Word History

Etymology

Italian Italia irredenta, literally, unredeemed Italy, Italian-speaking territory not incorporated in Italy

First Known Use

1914, in the meaning defined above