Gaijin ("outsider", "alien") is a Japanese word for foreigners and non-Japanese citizens in Japan, specifically non-East Asian foreigners such as white and black people. The word is composed of two kanji: gai ("outside") and jin ("person").

Some feel the word has come to have a negative or pejorative connotation, while other observers maintain it is neutral. "Gaikokujin" ("foreign-country person") is a more neutral and somewhat more formal term widely used in the Japanese government and in media.

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