The Collaborative International Dictionary of English v.0.48:

Reformatory \Re*form"a*to*ry\ (-t?*r?), a.
   Tending to produce reformation; reformative.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Reformatory \Re*form"a*to*ry\, n.; pl. -ries (-r?z).
   An institution for promoting the reformation of offenders.
   [1913 Webster]

         Magistrates may send juvenile offenders to
         reformatories instead of to prisons.     --Eng. Cyc.
   [1913 Webster]

WordNet (r) 3.0 (2006):

reformatory
    adj 1: tending to reform; "reformative and rehabilitative
           agencies"; "reformatory punishment" [syn: reformative,
           reformatory]
    n 1: correctional institution for the detention and discipline
         and training of young or first offenders [syn:
         reformatory, reform school, training school]