ADULT', noun [Latin adultus, grown to maturity, from oleo, to grow; Heb. to ascend.] Having arrived at mature years, or to full size and strength; as an adult person or plant. ADULT', noun A person grown to full size and strength, or to the years of manhood. It is also applied to full grown plants. among civilians, a person between fourteen and twenty-five years of age.
Source: Webster's 1828 American Dictionary ↗ · public-domain · returned verbatim, no AI