There are various definitions of adulthood, legal, spiritual and social. In some religions adulthood begins at age 13, in other it may be different or not recognised at all
…. Legally, many countries have specific legislation, the most prevalent age in the west is 18. Socially, it is much more difficult to define a specific age but is often considered that age when a person accepts responsibility, especially for their own acts or omissions. This obviously can vary between individuals and can also be considered a sign of maturity. ( Full Answer )