Seijin

Seijin is a Japanese term that means an adult, referring to a person who has reached adulthood. It is formed from the characters for “become” (成) and “person” (人) and is read as seijin. The noun is most commonly written as 成人, and it appears in phrases such as seijinshiki (成人式), the Coming of Age Ceremony.

In Japan, seijin is used in legal and social contexts to describe people who are considered adults. The country’s official age of adulthood has historically been 20. In 2022, the legal framework was revised so that many aspects of adulthood were lowered to 18, but the annual Coming of Age Day ceremony continues to celebrate those who have reached age 20. The Seijin no Hi ceremony, typically held on the second Monday of January, remains a national tradition in which 20-year-olds participate in local events, speeches, and often traditional or formal dress.

The term also appears in other uses related to adulthood, including media classifications such as seijin eiga, meaning adult or pornographic films. In general discourse, seijin can refer to adults in contrast to minors, and appears in contexts ranging from education and employment to social rights.

See also: Seijinshiki (Coming of Age Ceremony), Coming of Age Day, age of majority, Civil Code.