WordNet (r) 3.0 (2006):

therapist
    n 1: a person skilled in a particular type of therapy [syn:
         therapist, healer]

Moby Thesaurus II by Grady Ward, 1.0:

18 Moby Thesaurus words for "therapist":
   advisor, analyst, bonesetter, chiropractor, healer, homeopath,
   homeopathist, medic, midwife, oculist, optometrist, osteopath,
   psychiatrist, psychoanalyst, psychologist, psychotherapist, shrink,
   therapeutist