+ Terms for Zainichi Koreans	Holding North Korean nationality (also used regardless of nationality)
Hangul	재일조선인
Hanja	在日朝鮮人
Revised Romanization	Jaeil Joseonin
McCune-Reischauer	Chae'il Chosŏnin
Kanji	在日朝鮮人
Rōmaji	Zainichi Chōsenjin
Holding South Korean nationality
Hangul	재일한국인
Hanja	在日韓國人
Revised Romanization	Jaeil Hangugin
McCune-Reischauer	Chae'il Hankukin
Kanji	在日韓国人
Rōmaji	Zainichi Kankokujin
Regardless of nationality (in Korea)
Hangul	재일동포
Hanja	在日同胞
Revised Romanization	Jaeil Dongpo
McCune-Reischauer	Chae'il Tongpo
Regardless of nationality (in Japan)
Kanji	在日コリアン
Rōmaji	Zainichi Korian

Koreans in Japan are the ethnic Korean residents of Japan. They currently constitute the largest ethnic minority group in Japan. The majority of Koreans in Japan are Zainichi Koreans, also often known as Zainichi for short, who are the permanent ethnic Korean residents of Japan. Strictly speaking, the term "Zainichi Korean" refers only to long term, permanent residents of Japan who have retained either their Joseon (old, undivided Korea) or South Korean nationalities, not Korean-Japanese, or ethnic Koreans who have acquired Japanese nationality through naturalization.

The Japanese word Zainichi itself means "staying in Japan." For example, Zainichi-Gaikokujin (在日外国人) refers to "foreign nationals living in Japan", while Zainichi-Beigun (在日米軍) refers to United States Forces Japan. However, "Zainichi" on its own usually refers to Zainichi Koreans because of their significant presence in Japanese society.