Definition of acrasia:
(n) :
(archaic, rare) Lack of self-control; excess, intemperance; also, irregular or unruly behaviour.
(n) :
(philosophy) Alternative spelling of akrasia (“(uncountable) lack of physical or (especially) mental strength; poor willpower; also, the tendency to act contrary to one's better judgment; (countable) an instance of this”) [(philosophy, uncountable) Lack of physical or (especially) mental strength; poor willpower; also, the tendency to act contrary to one's better judgment; (countable) an instance of this.]