bandwagon

[dianeh]

What does the phrase 'jumping on the bandwagon' mean & where does the phrase originate?

[FredPuli]

It means to associate with some cause belatedly. The suggestion in the expression is that the person doing so is not sincere but merely hoping to gain advantage from associating himself in the public mind with the cause only once it looks a winner. Such a person is late in joining because he waits to see whether it is popular or not. The image is from a political parade headed by the band which is on a truck or wagon. It is an obvious focus of attention. These latecomers to the cause are not in the procession as originally formed but jump on to the wagon later en route to show their support and, importantly for them, to be seen giving it . If the parade appears unpopular they don't jump on.The expression is American in origin.