The Collaborative International Dictionary of English v.0.48:

Recidivist \Re*cid"i*vist\ (r[-e]*s[i^]d"[i^]*v[i^]st), n.
   One who is recidivous or is characterized by recidivism; an
   incorrigible criminal. -- Re*cid`i*vis"tic
   (r[-e]*s[i^]d`[i^]*v[i^]s"t[i^]k), a.
   [Webster 1913 Suppl.]

         The criminal by passion never becomes a recidivist, it
         is the social, not the antisocial, instincts that are
         strong within him, his crime is a solitary event in his
         life.                                    --Havelock
                                                  Ellis.
   [Webster 1913 Suppl.]

WordNet (r) 3.0 (2006):

recidivist
    n 1: someone who is repeatedly arrested for criminal behavior
         (especially for the same criminal behavior) [syn:
         recidivist, repeater, habitual criminal]
    2: someone who lapses into previous undesirable patterns of
       behavior [syn: recidivist, backslider, reversionist]