The Collaborative International Dictionary of English v.0.48:

Juvenility \Ju`ve*nil"i*ty\, n.; pl. Juvenilities. [L.
   juvenilitas: cf. F. juv['e]nilit['e].]
   [1913 Webster]
   1. Youthfulness; adolescence. --Glanvill.
      [1913 Webster]

   2. The manners or character of youth; immaturity. --Glanvill.
      [1913 Webster]