noun

1. a method, developed by Freud and others, of investigating mental processes and of treating neuroses and some other disorders of the mind: it is based on the assumption that such disorders are the result of the rejection by the conscious mind of factors that then persist in the unconscious as repressed instinctual forces, causing conflicts which may be resolved or diminished by discovering and analyzing the repressions and bringing them into consciousness through the use of such techniques as free association, dream analysis, etc.
2. the theory or practice of this

Etymology: ModL: see psycho- & analysis