An urge to do something inadvisable / An insatiable desire / An irresistible compulsion. Derived from Mid 16th century Latin / Greek kakoēthes ‘ill-disposed’, from kakos ‘bad’ + ēthos ‘disposition’.
Example
Even smart people who follow diet plan also occasionally succumb to the cacoethes of eating junk food.
Jake’s cacoethes of talking out of turn caused a number of distractions in the classroom.