Noun

(en noun)

A person who lives in an region undergoing a change of sovereignty and thus may choose between retaining their old citizenship or opting for the citizenship of the new sovereignty.

* {{quote-book

, year= 1914 , year_published= , author= W. R. Prior , by= , title= Oxford Pamphlets: North Sleswick under Prussian Rule , url= http://books.google.com/books?id=AwUxAQAAMAAJ&pg=PA103 , original= , chapter= , section= , isbn= , edition= , publisher= Oxford University Press , location= London , editor= , volume= , page= 9 , passage= According to one authority, nearly 40,000 of the Sleswick Danes had become 'optants' —that is, had taken the 'option' of Danish nationality—or had emigrated, by the end of 1880. }}

A person who opts into, out of, or for something.

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