The Collaborative International Dictionary of English v.0.48:

Rehabilitation \Re`ha*bil`i*ta"tion\ (-t?"sh?n), n. [Cf. LL.
   rehabilitatio, F. R['e]habilitation.]
   The act of rehabilitating, or the state of being
   rehabilitated. --Bouvier. Walsh.
   [1913 Webster]

WordNet (r) 3.0 (2006):

rehabilitation
    n 1: the restoration of someone to a useful place in society
    2: the conversion of wasteland into land suitable for use of
       habitation or cultivation [syn: reclamation, renewal,
       rehabilitation]
    3: vindication of a person's character and the re-establishment
       of that person's reputation
    4: the treatment of physical disabilities by massage and
       electrotherapy and exercises