adulthood; age of majority
Specifically refers to reaching the age of 20, which was the legal age of adulthood in Japan until 2022. Now largely historical or used in contexts referring to the traditional coming-of-age.
In Japan, adulthood was once defined as age 20.
A person who has reached the age of majority is legally considered an adult.
丁年 is a Sino-Japanese compound. 丁 (てい) can mean 'adult' or 'able-bodied man', and 年 (ねん) means 'year' or 'age'. The exact historical derivation is uncertain, but the term has been used in legal and literary contexts to denote the age of full legal capacity.