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definitions

Issei

or is·sei

[ees-sey]

noun, plural Is·sei or is·sei.

a Japanese person who immigrated to the U.S. or Canada after 1907 and was not eligible until 1952 for citizenship.
any Japanese immigrant to the U.S.
Compare Kibei, Nisei, Sansei.

Origin of Issei

1935–40; < Japanese, equivalent to is first + sei generation (earlier it-sei, it-seĩ < Middle Chinese, equivalent to Chinese yì one + shēng birth)
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
Word Origin and History for issei

Issei

c.1930s, term used among Japanese immigrants for first-generation immigrants, in Japanese, literally "first generation," related to ichi "one."

Online Etymology Dictionary, © 2010 Douglas Harper