noun
Refers to a person who has reached legal adulthood (age 20 in Japan, though the age of majority was lowered to 18 in 2022). Also used generally for a fully grown person.
日本では、成人は二十歳からです。
In Japan, adults are from age 20.
成人向けの映画です。
It's a movie for adults.
noun, noun or participle which takes 'suru', intransitive verb
coming of age; becoming an adult
Used as a noun or as a suru-verb (成人する) to describe the process of reaching adulthood. Often associated with ceremonies like 成人式 (Coming of Age Day).
彼は今年成人します。
He will come of age this year.
成人を迎える若者たち。
Young people reaching adulthood.