And then a psyco is a psychotic person who acts in a strange or dangerous manner.Then the definition of psychosis is a mental state described as a loss of touch with reality. People with this disorder are called psychotic.People experiencing psychosis may have hallucinations or delusions and may exhibit changes in their personality and disorganized thinking. These symptoms may be accompanied by an unusual or strange behavior, as well as by difficulty interacting socially and inability to carry out activities of daily living.