Significado de "Fall Off the Wagon"

When someone is said to have fallen off the wagon, it means that he or she did something which he or she had pledged not to do. This term is often used in the context of drinking; people who try to quit drinking may struggle and fall off the wagon at some point in response to stress, social temptation, and other factors. This idiom can, of course, also be used to describe participation in other forsworn activities, or a failure to keep a vow to do something.