psychotherapy Syllabification: (psy·cho·ther·a·py)Pronunciation: /ˌsīkōˈTHerəpē/Translate psychotherapy | into German | into Spanish Definition of psychotherapy noun the treatment of mental disorder by psychological rather than medical means. Derivatives psychotherapeuticPronunciation: /-ˌTHerəˈpyo͞otik/ adjective psychotherapistPronunciation: /-ˈTHerəpist/ noun psychotherapy in other Oxford dictionaries Definition of psychotherapy in the British & World English dictionary