Maniacal-depressive insanity
Black's Law Dictionary · Henry Campbell Black, M.A. · 1910
Black's Law Dictionary
A form of insanity characterized by alternating periods of high maniacal excitement and of depressed and stuprous conditions in the nature of or resembling melancholia, often occurring as a series or cycle of isolated attacks, with more or less complete restoration to health in the intervals. (Kraepeiin.) This is otherwise called "circular insanity" or "circular stupor."