ca·pri·cious
 /kəˈprıʃəs/  adj   [more ~; most ~]
   formal  
  1 : changing often and quickly
   capricious weather/winds
  especially : often changing suddenly in mood or behavior
   employees who are at the mercy of a capricious manager
  2 : not logical or reasonable : based on an idea, desire, etc., that is not possible to predict
   The court ruled that the punishment was arbitrary and capricious.
  ca·pri·cious·ly  adv  
   a manager who acts capriciously
  ca·pri·cious·ness  noun   [  noncount  ]