psychogeriatric

/ ˌsaɪkəʊdʒɛrɪˈætrɪk /

adjective

1. technical_term.
   (of an older person) no longer in touch with everyday realities; exhibiting delusions; mentally incompetent

noun

1. 1. a confused old person
   2. an impersonal label for a patient, as a unit, requiring institutional services appropriate for a mentally disordered old person