The Collaborative International Dictionary of English v.0.48:

Psychiatria \Psy*chi`a*tri"a\, Psychiatry \Psy*chi"a*try\, n.
   [NL. psychiatria, fr. Gr. ? the mind + ? healing.] (Med.)
   The application of the healing art to mental diseases.
   --Dunglison.
   [1913 Webster]