pubescent adj.

early 15c., "the coming or attainment of puberty," from Medieval Latin pubescentia, abstract noun from Latin pubescentem (nominative pubescens), present participle of pubescere "grow up; ripen, come to maturity; reach the age of puberty, arrive at puberty," from pubes "adult, full-grown" (see pubis). Biological use in reference to hairiness or soft down is by 1760 of plants, 1826 of insects, etc.

also pre-pubescent, "being or occurring before the onset of puberty," 1883 (in Gerald Massey's "The Natural Genesis"), from pre- "before" + pubescent. An older word in the same sense was impuberal (1829), from Latin impubes.