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nisei; second-generation Japanese (or Korean, etc.); person of Japanese parentage with non-Japanese citizenship
the second (e.g. Edward II)
son
「二世」 has another reading with different meanings.
彼女は日系二世として育った。
She grew up as a second-generation Japanese.
二世が親の言語を失うことは珍しくない。
It's not unusual for second-generation immigrants to lose their parents' language.
二世の若者たちは二つの文化の間で揺れることがある。
Second-generation youth sometimes waver between two cultures.