Source : Webster's Revised Unabridged Dictionary (1913)

Juvenile \Ju"ve*nile\ (?; 277), a. [L. juvenilis, from juvenis
   young; akin to E. young: cf. F. juv['e]nile, juv['e]nil. See
   {Young}.]
   1. Young; youthful; as, a juvenile appearance. ``A juvenile
      exercitation.'' --Glanvill.

   2. Of or pertaining to youth; as, juvenile sports.

   Syn: Puerile; boyish; childish. See {Youthful}.

Juvenile \Ju"ve*nile\, n.
   A young person or youth; -- used sportively or familiarly.
   --C. Bront['e].

Source : WordNet®

juvenile
     n : a youthful person [syn: {juvenile person}] [ant: {adult}]

juvenile
     adj 1: of or relating to or characteristic of or appropriate for
            children or young people; "juvenile diabetes";
            "juvenile fashions"
     2: displaying or suggesting a lack of maturity; "adolescent
        insecurity"; "jejune responses to our problems"; "their
        behavior was juvenile"; "puerile jokes" [syn: {adolescent},
         {jejune}, {puerile}]