1. The state of being at variance and without harmony and congruence among parts, elements, or things: Many times, the nice restaurant in town had wonderful and delicious meals, but its inconsistency of serving such good food discouraged a lot of customers and so they went elsewhere to dine.
2. The contradiction or discrepancy between ideas or propositions: Jane told her friends that she was on a diet, but ate lots of ice cream and donuts instead which showed much inconsistency in what she said and what she really did.