- of, pertaining to, characteristic of, or suitable or intended for young persons: juvenile books.
- young; youthful: juvenile years.
- immature; childish; infantile: His juvenile tantrums are not in keeping with his age.
- a young person; youth.
- a youthful male or female role.
- an actor or actress who plays such parts.
- a book for children.
- Ornithology. a young bird in the stage when it has fledged, if altricial, or has replaced down of hatching, if precocial.
- a two-year-old racehorse.
- young, youthful, or immature
- suitable or designed for young peoplejuvenile pastimes
- (of animals or plants) not yet fully mature
- of or denoting young birds that have developed their first plumage of adult feathers
- geology occurring at the earth’s surface for the first time; newjuvenile water; juvenile gases
- a juvenile person, animal, or plant
- an actor who performs youthful roles
- a book intended for young readers
1620s, from Latin iuvenilis “of or belonging to youth,” from iuvenis “young person,” originally “young” (cf. French jeune; see young). Juvenile delinquency first recorded 1816; Juvenile delinquent the following year.