The Collaborative International Dictionary of English v.0.48:

Rejuvenation \Re*ju`ve*na"tion\ (-n?"sh?n), n.
   Rejuvenescence.
   [1913 Webster]

WordNet (r) 3.0 (2006):

rejuvenation
    n 1: the phenomenon of vitality and freshness being restored;
         "the annual rejuvenation of the landscape" [syn:
         rejuvenation, greening]
    2: the act of restoring to a more youthful condition

Moby Thesaurus II by Grady Ward, 1.0:

24 Moby Thesaurus words for "rejuvenation":
   new birth, palingenesis, palingenesy, reanimation, rebirth,
   recrudescence, refreshment, regeneracy, regenerateness,
   regeneration, regenesis, rejuvenescence, renaissance, renascence,
   renewal, resurgence, resurrection, resuscitation, revival,
   revivescence, revivescency, revivification, second wind,
   second youth