Subadult

Subadult is a term used across biology, archaeology, forensic science, and law to describe an individual or organism that has not yet reached full maturity or adulthood. The exact meaning varies by field, but it generally signals a developmental stage between infancy or juvenilehood and full reproductive maturity.

In human contexts, subadult typically refers to people below the age of adulthood. Legal definitions of adulthood vary by jurisdiction and purpose (such as consent, criminal responsibility, or civil capacity), so the subadult category is not fixed. In professional and policy discussions, subadult status is often distinguished from adulthood to emphasize developmental, rather than legal, considerations.

In biology and ecology, subadult denotes a life stage between juvenile and adult. Subadults may still be growing and may not yet be sexually mature. This usage applies to a wide range of species, including birds, mammals, reptiles, and insects, each with its own timelines for growth and maturation. In paleontology and archaeology, subadult bones or remains indicate individuals who were not biologically mature at death.

Forensic contexts use subadult age estimation to describe individuals who are not yet adults. Age assessment relies on developmental markers such as dental eruption, epiphyseal fusion, and other skeletal features, which differ from adult aging methods.

See also: age of majority, juvenile, adolescence, development.