also: ナショナルスト
noun
A person who strongly identifies with their nation and often advocates for its interests, sometimes with a connotation of extreme patriotism.
彼は熱心なナショナリストで、自国の文化を誇りに思っている。
He is an ardent nationalist and takes pride in his country's culture.
その政治家はナショナリスト的な政策を掲げて選挙に勝った。
The politician won the election by advocating nationalist policies.
Borrowed from English 'nationalist', adapted into Japanese katakana. The variant ナショナルスト reflects an older or alternative transcription of the English word.